Aoi Nishimori is a high school girl who lives alone in her own apartment, but to her surprise, she discovers that the prince of her school, Shusei Kugayama, has moved in next door To add to this, a series of crazy happenings result in the two living together under a single roof Shusei is known to be a heartless guy and Aoi particularly hates him after he coldly rejected her best friend, so a life of cohabitation seems like a recipe for disaster. And yet, Aoi somehow can't stop her heart from pounding when she's with Shusei...