On his first day of junior high, Kei Enjoji fell in love at first sight. His heart was immediately captured by the gorgeous Ranmaru Samejima, a young kendo prodigy, and the two slowly formed a deep romantic bond. Now adults and living happily together as a couple, things seem to be going well for Ranmaru and Kei.

One morning, host Kei arrives home after a night out drinking with a client. A frequent occurrence, Ranmaru is initially unfazed by Kei's drunken state—until he notices three extremely suspicious things: Kei's clothing smells of makeup, his chest is stained with lipstick, and he is carrying matches branded with the name of a love hotel. To top it all off, a woman calls the apartment asking for "Kei-chan," and at that, Ranmaru loses it.

Hurt by Kei's unfaithful actions, Ranmaru storms off. He spends the day reminiscing about years of precious memories, deciding to put them behind him for good—and when he is "picked up" by a woman on the streets, he comes to terms with reality. If this is what society wants, and if Kei has truly fallen for a woman, then who is he to stand in their way?