A cowardly, useless shut-in with nothing but evil thoughts in his head—yet too timid to act on them—inherits the memories of a demon cultivator and is reincarnated into the body of an even more timid and cowardly menial worker in a necromancy department at a magical martial arts academy in another world.

This weak little menial, in order to improve his own strength, quietly cultivates demonic arts, while also practicing necromancy and dark magic...

Unbeknownst to all, the little menial grows rapidly, constantly overturning everyone’s expectations...