My Self - Insert Stash

-Good afternoon! I've got you guys another SI Naruto but this one is quite fun, refreshing and overall a different take on SI Naruto, check it out!

Synopsis: Kenji enjoyed living, in fact he enjoyed just existing in general. He has only existed for less than a day, but he decided to make it his goal to live a long and full life. "Naruto and the rest can take care of the villains, I'll enjoy myself as a simple craftsman." Cultivator OC/ Reincarnated OC/ Monk OC. Crafting Game Elements.

Rated: M

Words: 184K

Posted on: fanfiction.net/s/12901674/1/Kenji-the-Shinobi-Craftsman(Redwall6921)

-I'll be putting the chapter ones of all the fanfics mentioned, to give you guys a sample if you wan't more please do go to the website and support the author! (And maybe even convince them to start uploading chapters in here as well!)

Chapter 1

A/N: This is Naruto Fanfic, with elements of Xianxia Cultivation Novels but it won't have things like grandmasters, spirit beasts, ancient plants, ridiculous overpowered sect leaders, or even cultivators apart from the MC and those he teaches his art. This also has a video game crafting system that is exclusive for the MC.

MC is a reincarnated OC that is a mixture of his past life and the new body he inhabits.

Chapter 1

Kenji Yamamoto woke up with a start. Looking around him he could see that he had passed out in the middle of some street and there were already some people around him trying to help him to his feet.

Dazed he was helped to a sitting position and as the people began to talk, he looked even more confused. They spoke a language he didn't understand and were dressed weirdly, like those pictures of what ancient japan used to look like. Looking at his hands for a moment he was shocked to see that they looked young, way to young to belong to a twenty-year-old blacksmith apprentice.

Just as he felt the panic raise in his c.h.e.s.t, he was bombarded by a set of memories that we not his own. Grabbing at his head he tried to alleviate the blinding headache, feeling as if someone had shoved a knife in his brain.

"Hey kid, are you okay?"

"Anyone see what happened?"

"Quick! Give him some space!"

"Is he going to be alright?"

He looked at them again in astonishment, he could understand them now. Kenji let them guide him to a nearby dango shop and once they were sure he was okay, left him there but not before buying him a stick or two of dango.

Looking at his hands again he was confused again. Kenji now had two sets of memories.

One belonged to that of a twenty-year-old a.d.u.l.t man that ironically enough was named also Kenji. This Kenji however was an apprentice to one of the last traditional blacksmiths in Japan. Okay, so by apprentice, he meant slave, being the youngest and also the grandson of the master meant that he was expected to follow all of his orders. It was a family business, so it was not like he could say no, not without disappointing his family anyways. Despite this, Kenji did enjoy the old way of forging and found meaning in the traditions that had been passed down for generation to generation, however he did have a very normal childhood. The young man also read a number of novels and even wrote a few, xianxia novels mostly.

The next set of memories were of that of a ten-year-old boy, who's body he now inhabited. This Kenji Yamamoto was an orphan who had lost his parents during the kyuubi attack like so many others. That being said, he lived at one of the newly built orphanages following the attack, until he was old enough to enroll in the local ninja academy, where he was given an apartment. Kenji was in the same year as Naruto and the rest of the clan heirs but was in a different classroom, only having seen them twice in his entire time at the academy. The ten-year old was ranked below average in his class, but not the worst, the only thing that really stood out was his short and chubby appearance.

Taking everything in at once the new Kenji had thought that one the memories must have been false because the first set of memories told him that this was the Naruto universe, a fictional world that was a popular manga and anime, but the other one told him it was all real. As he looked around the shop, he saw a number of these shinobi with Leaf Headbands talking and eating their meals, he couldn't deny the fact that they were real.

So in the end he had come to a conclusion, he had somehow ended up in a fictional world, and was training to be a killer. Instinctively, Kenji knew that he was no longer the young boy or the man, instead he was a mixture of both. He tried to wrap his head around it but decided to give it up, he was there now and his predecessors A and B as he now referred to them were long gone, having been absorbed into his personality.

He ate the last of his dango trying to absorb everything he knew about the new world he was in, exactly like a newborn child. Looking at the wooden skewer in his hand he tried to observe it and something amazing happened, information that was not there before appeared in his head.

Dango Stick

Quality: Poor

Attack: 3

Chakra Points Needed to Upgrade: 1

"Huh?"

The small ten-year-old looked on in wonder, he did know what to think as this was something entirely new to him, neither of his sets of memories had any information about this strange phenomenon.

Kenji stood up and began to walk away from the shop letting his feet carry him to his destination all the while staring at the wooden stick.

In no time at all he arrived at a worn-down apartment complex. Looking at it curiously he wanted to ask what he was doing there before the memories from Kenji B (Boy) told him that this was his home. All the orphans that chose to enter the Academy had been given a room in one of these apartments and would receive a monthly stipend, until they became genin. Once they did become genin they would be expected to pay back everything that they had spent during their time there.

Taking out a key from his pocket, he went to his room which was on the first floor, behind the door with the sign that said 1-B. Stepping inside, the first thing that he noticed was the smell, it appeared like his predecessor was not a fan of cleaning. The young reincarnator could see a mountain of dirty dishes in the sink, bundles of garbage bags littered the entrance, and the floor was covered in used candy wrappers and ramen cups. Taking a finger, he slid it on the counter and saw a trail of dust left behind. The entire room was simple, with it only having a living room/bedroom, a kitchen with a counter, and a bathroom.

"I must clean," the boy stated as he rolled up his sleeves and began to go about the room trying to clean and organize everything as much as possible, his memories of Kenji A (A.d.u.l.t) helped him in this regard. He washed the dishes and started to walk around the room with a garbage bag to pick up all of the trash. Once he had everything bundled up, he took everything to the large garbage bins outside.

Borrowing some cleaning supplies from his landlord, a nice old lady that was shocked to see him ask for cleaning supplies, he went about the entire room with a wet rag and scrubed the floors as much as he could. Despite all the chores he was doing, he did them with a smile. Having the memories was not the same thing as doing it for the first time, and this was still a new experience for him since his birth about forty minutes ago.

Once he was done cleaning the living room, kitchen, bathroom, and his bed; he finally stopped to inspect himself in the mirror.

Kenji thought that his looks had much to be d.e.s.i.r.ed, he was short, standing at about 4'4''. Looking down at his stomach he also noticed that he was actually quite fat (around 110 pounds) and his face was also very round on account of his chubby cheeks. He had slanted fox eyes that looked like they were closed all the time. (-_-) His hair was a greasy brown and had a multitude of knots and split ends. Looking at his clothes he saw that he was wearing a dirty green yukata. Lifting one of his sleeves to his nose, Kenji almost gagged with how bad it smelled. (Look up Arita Haruyuki from Accel World, but with closed fox eyes.)

Giving himself one last look in the mirror he turned to the bathroom, "This can not go any longer. I don't know what my predecessor was thinking living like this. Thankfully the memories of my older half are here to guide me."

Kenji spent twenty minutes scrubbing himself raw using the hottest water possible in order to make sure he was clean. Getting out of the shower he went to the closet and found the only pair of clothes that were even remotely clean, green shorts, a white shirt.

"Now what?" Kenji said out loud to himself. Now that he was alive, he didn't know what he should do. Feeling a rumble and pain in his stomach he looked down and asked "Is this hunger? I know about it from the memories, but this is the first time experiencing it."

"Food! I should get food!" the small boy said to himself as he raced to the kitchen and got out a box that had some type of sugar cereal. Taking one of the small marshmallows from the box he looked at it carefully before placing it on the tip of his tongue, then began to gently roll it around in his mouth, trying to get a clear favor. It was sweet, way sweeter than the dango he had eaten earlier, and it dissolved very quickly. Gulping down the now dissolved marshmallow he had a smile on his face, "No wonder boy me liked them so much, these are delicious. What else is there?"

Putting the rest of the cereal on the counter, he walked to his small fridge and looked at what was inside. It didn't have very much but there were still some things there that he could try.

Grabbing everything in his short pudgy hands he sat on the ground and spent the next half hour just taste testing everything, while the memories of his past selves told him what they tasted like, he wanted to do it with his own taste buds. The first thing was a red plastic bottle that had a picture of a red ripe tomatoes. Popping the lid, he tipped the opening into his mouth and drank deeply from it, savoring the texture and flavor. "It's sweet, and acidic."

Putting down the ketchup bottle, he picked up a green pepper of some sort. His memories told him that it did not taste good, but he was adamant on trying it anyway, wanting to find out for himself. Gently he took a small bite from the green pepper and immediately felt his face start to heat up. Touching his lips and tongue he felt them start to go numb, "Ow, ow, ow, this hurts." The taste of the spicy object had spread all around his mouth now, and he started having a hard time breathing. With a hand he whipped away the sweat that had started to collect on his brow.

Kenji finally decided that he should stop the pain, so he got on the small stepping stool in order to reach the sink and after turning the water faucet on he drank deeply, sinking his entire head. Despite the burning pain he felt on his face, the small boy still had a large grin making him look like a fox with closed eyes. To him it was a new experience and it was a wonderful feeling of being alive.

Once he was done experimenting with the food, he began to search the apartment for anything that was useful.

Sitting on the foot of a small twin sized bed that was placed against the farthest wall of the room, he spread the few belongings he had on the sheets writing down on a separate piece of paper what he had.

15 practice shuriken

7 practice kunai

Academy books

71,470 Ryo

Two ninja mesh shirts

Ninja sandals

Red Bandana

Closing his eyes completely, not that anyone would notice an account that they always looked closed, he began to browse through the memories of Kenji B.

From what he could tell, Kenji B had joined the academy back when he was 6 like the rest of the orphans. He was put into one of the spare class with other orphan kids, along with those kids who came from low income families.

The Academy was divided into six years 1-6, each year had 9 classrooms labeled from A-I, and each classroom held 27 students. From his math, that meant that there was 1,296 students in the entire school. He was in class 4-G, a class that was mostly made up of orphans that didn't come from a clan and as a result, received less attention than those from classrooms like 4-A that currently had all the clan heirs.

The amount of Ryo was also a welcomed sight since it meant that he had at least some amount of resources. Apparently Kenji B was a very greed pig, and only used the b.a.r.e minimum of his money when ever possible. Case in point was the pantry that was full of cheap and unhealthy foods, like instant ramen and ch.i.p.s. It was no wonder that he had grown fat living off the stuff for the past five years. From his calculations the value of a single Ryo went something like this.

1 Ryo= 10 Yen

1Ryo= $ .10

He got 2,000 Yen every month for spending money. He was expected to shop for his own groceries since the gas, water, lights, and room was already taken care of. His small saving was a result of four and a half years of careful budgeting.

Looking at the equipment spread out on his bed he picked up a wooden kunai and examined it careful. Just like before, information popped into his head.

Wooden Practice Kunai

Quality: Ordinary

Attack: 10

Chakra Points Needed to Upgrade: 18

Putting down the Kunai he thought about this strange feeling.

"Chakra Points? Does that mean I just add chakra," he said pensively? As a fourth-year academy student he already knew how to channel chakra, although he didn't have very large reserves according to his sensei.

Grabbing the kunai again he decided to test this theory by channeling the chakra into the wooden shaped knife with the intention of 'Upgrading it'. Once he started to feed it his chakra it drank greedily, and he felt his reserves plummet to fifth of what they were.

Upgrade Success

Wooden Practice Kunai + 1

Quality: Ordinary

Attack: 10

+5 Attack

Chakra Points Needed to Upgrade: 20

Getting another Kunai to compare, he couldn't see the difference with just looks alone. They looked identical, the only noticeable difference was that the upgraded version felt sturdier in his hands.

Kenji fed the kunai more chakra, hopping to see more of what it would do. He was able to upgrade 3 more times before he felt his reserves drop dangerously slow.

Upgrade Success

Upgrade Success

Upgrade Success

Wooden Practice Kunai + 4

Quality: Ordinary

Attack: 10

+ 23

Chakra Points Needed to Upgrade: 26

Now it had triple its original attack power. As a test he took the normal kunai and launched it at the wall, closely followed by the upgraded version. The first one bounced off the wall harmlessly like he expected, but the knew upgraded version managed to lodge itself about 2 cm in before falling to the floor too.

Taking out the dango stick from before, he observed it again.

Dango Stick

Quality: Poor

Attack: 3

Chakra Points Needed to Upgrade: 1

Kenji curiosity was peeked, and he wanted to see what it would do if he upgraded it.

Upgrade Success

Upgrade Success

Upgrade Success

Upgrade Success

Upgrade Success

Upgrade Success

Dango Stick + 6

Quality: Poor

Attack: 3

+22

Chakra Points Needed to Upgrade: 2

That was his last thought before he felt a headache and passed out.

Opening his eyes again, or at least as wide as they let him, he noticed that it was night already. He felt his body ache, almost as if he had run the academy training course five times without stopping. He then noticed that his chakra reserves were already back to full capacity, even more curiously it felt like it had grown by a small bit while he was asleep. From the memories of Kenji B, he knew that it should have taken him much longer to recover even his meager chakra reserves.

Looking over at the upgraded dango stick, he let out a snort of pride. It still weighed the same, but he noticed that the stick was much stronger than before. He tried to bend it as far as he could between his fingers, but even with both hands he only managed to bend it a little before it snapped back into place.

Gathering more chakra in his hands he fed it some more energy in hopes to see just how far he could level it up.

Upgrade Failed

Dango Stick + 5

Quality: Poor

Attack: 3

+19

Chakra Points Needed to Upgrade: 2

"It seems that it can fail too. It also went down a level," he said as he contemplated his next choice of action. "I might as well see how far I can go."

Kenji upgraded it again, and this time it was a success, bringing it back to +6. He continued to level it until it reached +9, but when he tried to level it to +10 he failed again, only this time instead of it going back a level it crumbled to dust in his hands.

He was disappointed since he had spent so much of his time on that stick.

After cleaning the dust from his bed, he retrieved more dango stick that he had seen taken from the trash feeling they could be useful later on, which just so happened that it did.

Kenji was determined to make at least one of them a +10, the earlier failure only seemed to encourage him.

It took some time, but he completed it 20 minutes later. He had moved to bathroom so as to not make a mess. Each failure taught him something new. For example, once something reached +8 it could no longer level down and instead it turned into ash. Also, it was easier to level something up in the beginning, but each success only made the next one even harder. His reserves were almost empty again, but the fruit of his labors were finally in his hands, and what a fruit it was.

Dango Stick + 10

Quality: Poor

Attack: 3

+43

+10: A 5% chance of doubling it piercing power when thrown at a target.

Chakra Points Needed to Upgrade: 5

"So it seems to gain a buff after it reaches level 10. This reminds me of those crafting RPGs that Kenji A used to play back in his world," the small round boy said to himself. Looking through the memory of the young man in question, he could see that they indeed looked very similar. He was curious to see what else this ability gave him. "Could this be a kekkai genkai of some sort? Still, this is one weird ability."

'Now what?' he thought. That was the question he had been avoiding all day. Existence was new to him, and he didn't know what he should do.

He was the current Kenji, or Kenji C, but that didn't mean he wanted to be just like his predecessors, he was a mixture of both after all.

From what his memories of Kenji A said, it seems that this world had plenty of dangers both visible and hidden. His village, the Leaf Village, was one of the major powers in the entire continent, but it was also a huge target for many. He didn't fancy fighting people like Pein, Obito, Madara, and Kaguya, they terrified him. He was also unsure if he could take someone's life, half of his mind said that it was wrong, while the other said that if he wanted to survive in the world, he had to be willing to do it. And despite being new to it, he had grown accustomed to living and hoped to keep doing it for a very long time.

From what he knew of the show and manga, he hoped that he could hopefully avoid some of the major disasters that befell his home, like hiding during the Sound invasion or being out of town when Pein decided to add a crater in the middle of the village. He knew he could count on good old Naruto to win, the small boy would no doubt beat them again and then go on to become Hokage in the distant future.

If possible, he wanted to stay as a simple civilian since that meant that he wouldn't need to be in so much constant danger. He could even open up a store and make his living through blacksmithing, but it was then that he remembered that he was an Academy Student, he had signed a contract when he left the orphanage. Kenji knew that his only hope was to either become a non-descriptive genin level Ninja that stuck to doing mostly D and C- rank missions or retire early, something that he didn't even know if it was possible.

Looking at the stick in his hand, be began to get an idea. "Maybe if I open up a shop earlier, I can earn enough money to retire early and then move to a far away island. Leave all the fighting to Naruto and the rest of the shinobi, all I have to worry about is the Infinite Tsukuyomi cast by Madara but I'm sure that Naruto will find away to stop him like before. Plus, if by some chance he can't, living in a fake and perfect world doesn't seem like a bad way to go."

It was decided, he would try to avoid fighting a much as possible and open an equipment shop to help in his goals of being a civilian. Still that did raise some problems, "I wonder how much chakra I have? I'm going to need more equipment if I want to open up a shop but to do that, I need more chakra to upgrade the items."

Chakra: Academy Student

Chakra Points: 12/105

The information appeared in his head once he had asked the question.

"Nice," he said with a grin lighting up his round features.

He decided to make a plan of all the things he needed to accomplish if he hoped to live a long and prosperous life as a civilian, and once he was finished he went to sleep. It was Friday, so he had two days off before he needed to attend classes again.

(Next day)

Waking up, he started by doing morning stretches, his goal was to be able to touch his toes by the end of the month, a hard task for him.

After eating a mixture of things from the fridge he took half of his savings and decided to go shopping, plus he wanted to scout out the merchandise of the other stores.

He bid the old manager a goodbye before leaving.

Walking down the street he tried to get a sense of where he was but being waist level to many of the a.d.u.l.ts walking around made it difficult to see in the crowds. Finally, after some time he was able to make it the shop where he bought most of his equipment.

It was an old shop, manned by a single old man in his sixties. The man was simply called Old Shin by the customers and he doubted anyone knew his real name, not even Shin.

Opening the door, he heard the bell ring, indicating that someone had opened the door. Shin was hunched over as he stocked some of the shelves with more equipment. He was tall and thin, the large number of scars on his face and hands told him that the old man used to be a shinobi before becoming a shop owner. He was wearing a simple blue kimono with his white hair tied in a traditional top bun, making him look like one of those old samurais that Kenji A used to see in movies.

Shin nodded in his direction before going back to stacking the shelves.

It was no surprise that he was quick to being dismissed as a threat, his overall appearance wasn't in any way threating. A fat, short, and squinty eyed ten-year-old was hardly the most intimidating sight.

The shop was small, but it had a large variety of equipment ranging from swords to bo staffs, explosion tags to smoke pellets, even those supposed nasty tasting ration bars.

He browsed through the aisle scanning the weapons and armor. Picking up a long wooden bo staff from the stack in the corner he looked at it and the information poured to his head.

Bo Staff

Quality: Ordinary

Attack: 203

Chakra Points Needed to Upgrade: 48

Placing the staff back on the rack he began to look at more of the weapons and some of the armor.

Katana

Quality: Ordinary

Attack: 432

Chakra Points Needed to Upgrade: 80

Kunai

Quality: Ordinary

Attack: 160

Chakra Points Needed to Upgrade: 24

Tanto

Quality: Ordinary

Attack: 305

Chakra Points Needed to Upgrade: 45

Iron Arm Guard

Quality: Ordinary

Defense: 369

Chakra points Needed to Upgrade: 25

Chainmail Shirt

Quality: Ordinary

Defense: 85

Chakra Points Needed to Upgrade: 17

It was then that he stopped and stared at the display case that had a giant Najinata, easily nine feet tall.

Naginata

Quality: Low Human

Attack: 785

+Chakra Metal was added in the process of forging, making it stronger and sharper than normal weapons, it is chakra conductive.

Chakra Points Needed to Upgrade: 150

'So low human is the next level after Ordinary. It makes me wonder what quality one of the swords from the Seven Ninja Swordsman is at,' Kenji thought to himself as he made his way toward the counter at the back of the store.

Behind the counter were more weapons being displayed by hooks, as well as scrolls that looked like they might be used for sealing.

Shin who was seated in a chair behind the glass display counter, reading what he could tell was an Icha Icha Paradise book, didn't pay him any mind as he looked at all of the things behind the glass counter. There were small smoke pellets, chakra replenishing pills, solider pills, ninja wire, some type of food bar, and explosive seals.

Now that he thought about it, there was something that he had yet to see.

"Shin, can you give me one of those ration bars?" he asked as he began to take out the money from his dumpling shaped wallet.

Shin looked at him with an incredulous look, "You actually want one? Those things taste like cardboard mixed with dog shit. I've never heard of anyone actually eating one that wasn't half starving and delirious from hunger."

He shook his head up and down, "Yep."

Still looking skeptical shin got off his chair and reached behind the counter and took out a ration bar and placed it on the counter, "Fine kid. It's be 50 Ryo."

Putting the appropriate amount on the counter, he grabbed the bar that was wrapped in some shinny metal wrapping paper. He ripped one end open and the first thing to hit him was the awful smell of strong vitamins and minerals. Taking it fully out of the wrapper he saw that it was the same shape as a granola bar, but it looked and felt more like a piece of white chalk.

Shin had yet to take the money from the counter instead waiting for the boy's reaction of talking his first bite.

'So I can't upgrade food. That's a shame, but I guess that makes sense, I didn't upgrade that ketchup bottle yesterday after all,' the pudgy boy thought as he brought the bar closer to his mouth, curious to see if it was as bad as people made it out to be. Slowly he took a small bite, taking a fourth of the entire thing in his mouth and chewing it a bit.

He let it dissolve for a bit before moving it around in his mouth to get a clear flavor. Kenji's face stayed impassive as he found that it tasted like chalk, quickly drying up his mouth and throat. It was also very bitter and tasted like someone had mixed in powdered garlic and fish oil. "What an interesting taste and texture," he commented as he threw the rest of the bar into his mouth.

Once he was done eating, he turned to the aged ninja that was looking at him like he had grown an extra head. Then he looked behind him to see a small poster.

Ration Bar Challenge

Rules

1) Eat 20 Rations in 30 Minutes

2) Ration bars must be eaten plain without any additional flavors.

3) Only water can be drunk during the challenge

4) If you lose, you pay for all 20 Ration bars

Prizes:

1 Advanced Ninja pack

1 Equipment of Your Choice (5000 Ryo or lower)

3 Sealing scrolls

"Hey what's that," Kenji said as he pointed to the poster, wondering if he should join the challenge.

Shin looked behind him to see the poster before looking at the boy that could be more than 4 feet and a half, and looked as round as a beach ball. "The challenge? It's just a gimmick to sell more ration bars. No one's been able to beat it, although an Akamichi did come close a couple of years back. Got to 14 before he couldn't take it anymore and threw up all over the floor, not that I can blame him. Why? You want to try it?"

"Sure do. Here, it's 1,000 Ryo to enter right. Oh and I'll also take some water if you have any," the smiling boy said as he placed the money next to the stupefied man.

Shaking his head, Shin looked amused as he took the money and handed over the twenty ration bars, "Fine kid, just don't puke on my floor, or else I'll have you clean up the entire shop."

Kenji just nodded as he sat down against the counter, unwrapped the first bar and took a bite, thinking about what he had just learned about his new skill as well as making plans for his own store.

23:58 minutes later Kenji stepped outside the shop with one advanced Ninja Pack, a wooden jian (Chinese sword), 3 sealing scrolls, and a box full of ration bars as a gift. He had won the challenge, and his picture was being hung up on the wall by Shin. The pudgy boy was happy, he got to try something new and received a bunch of equipment without having to pay for it.

Now he just needed to shop for groceries and he could go home.

But as he was making his way to the supermarket, he saw something that caught his attention. A traveling monk was seated outside of some type of convince store meditating, people passing by would drop Ryo at his feet where a small cup was at. He would thank them and offer them a blessing.

Kenji A and B were never the religious kind, but Kenji C was willing to give it a try. He was proof that there really was something to this whole reincarnation thing after all. With that he made up his mind and headed to the direction of the sitting monk.

A/N: So I this is the first chapter of this fanfic I am working on. It began as just a silly idea after reading to many cultivation novels, but then slowly it began to grow into an actual fic.

My inspiration for this is from a Chines Novel called Upgrade Specialist in Another World. I liked how the MC could upgrade normal everyday objects until they could go against even the strongest weapons. He leveled a brick so much that it could defeat Cultivation Masters.

Anyways, this fanfic will obviously be different. First of all, cultivation has not been invented in this world. A cultivator in the Naruto Universe, I feel needs to gathering Nature Chakra into their bodies, but instead of letting it go, they slowly mix it into their body permanently.

Another thing is that like in most cultivation fanfic there will be certain levels that someone has to pass to reach the next level. Here's a brief overview:

Stage 1: Activating the chakra pathways.

Stage 2: Begin purifying the chakra

Stage 3: Fill the 1st chakra gate with purified chakra

Stage 4: Fill the 2nd chakra gate with purified chakra

Stage 5: Fill the 3rd

Stage 6: 4th

Stage 7: 5th

Stage 8: 6th

Stage 9: 7th

Stage 10: 8th

Each new stage will bring about new benefits such as stronger skin, aura, chakra reserves, even new elemental affinities.

As for the upgrade system the first three Ranks have been shown.

Poor, Ordinary, and Low Human

Next is the most Chakra Points, this is the normal amount for the average ranks. Obviously, this doesn't include people like Naruto or those with huge amounts of chakra.

Chakra points:

civilian 50

Academy student 500

genin 1000

Chunnin 2000

Jonin 3000

Kage 5000

Tailed beasts 10000+