Comprehensive Manga: The Strongest Demon King Beginning From Kuwang Academy

Roy traveled to the world of Demon High School and became Grefia’s younger brother, the only heir to the Lucifergus family.

And obtained the demon chess system, from then on Roy walked the road of crossing the world to conquer his family and become the strongest demon king.

Saeko Poshima: I swear by the honor of the Poshima family, I am willing to be Roy’s knight.

Butterfly Ninja: As long as I can save my sister, I am willing to be Roy’s soldier.

Esdes: If you want me to be your queen, then defeat me!

The main world is the world of Demon High School.

Across the World: Apocalypse of the Academy – Blade of Demon Slayer – Pokémon – Slashing Red Eyes – Dragon Maid of the Kobayashi Family – God Eater – To be continued