Karen Amakura is good at her job, but bad at love. The only one who seems to understand her is Rei, a kind and handsome man who always drinks with her at her favorite bar. One night, they both end up learning about their feelings for each other and one thing leads to another... Is she imagining it, or has Rei's personality changed? The man who she thought was a saint suddenly turned into a devil! Who exactly is Rei, and what does this sweet, but roller-coaster ride romance have in store for her...?