Senpai is a nerdy high schooler whose manga work is discovered by some loud girls in the library. They all tease him, but one among them, Nagatoro, takes it further than the others.

Nagatoro torments Senpai by threatening to suck his blood like a vampire and by making him play a nipple-finding game. Senpai escapes to a family restaurant, where he runs into Nagatoro and her friends and discovers something surprising.

Senpai awakens in another world, where he and Nekotoro set out on an adventure to defeat the demon king. Nagatoro invites Senpai to the beach.

Senpai isn’t sure he can beat the art club president in popularity at the culture festival. Nagatoro and the gang do everything they can to help him.