Deep in an abandoned Diamond facility lies a dormant Gem. However this Gem is waking up and it is no ordinary Gem...

Meet (Y/N), the most powerful hero on earth... that no one has ever heard of. He's done it all, slay monsters, avert disasters, and save the planet and if there is one thing he's learned is that he REALLY wants a break. After deciding to have a normal life, (Y/N) has chosen to finish high school. And what better place to have a normal school life than Honnouji Academy!!!! Anywhere... Literally anywhere else.