Thirty years ago a strange phenomenon called a "spacequake" devastated the center of Eurasia, claiming the lives of at least 150 million people. Since then, smaller spacequakes plague the world on an irregular basis. Shido Itsuka, a seemingly ordinary high schooler comes across a mysterious girl at the ground zero of a spacequake and learns she is one of the "Spirits" who are the real cause of the spacequakes that occur when they manifest themselves in the world. He is recruited to make use of his mysterious ability to seal the Spirits' powers thus stopping them from being a threat to mankind. However, there is a catch: to seal a Spirit's power, he must make her fall in love with him and kiss him.

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.