A cleaner who disposes of dead kaiju revives his childhood dream of fighting them instead. But the parasite kaiju inside him complicates his plans!

Staz is a vampire from the surreal "Demon World", and Fuyumi, an ordinary girl, accidentally wanders into the Demon World through a portal. Subsequently after meeting each other, Fuyumi is killed by a carnivorous plant and turned into a ghost, causing Staz to take responsibility and pledge to help bring her back to life.