Takahashi, an office worker who loves butts, is about to move and is going to look at a new apartment. Rio, the real estate agent, has an incredibly beautiful butt, and Takahashi's butt switch is turned on at first sight. While looking at the apartment, he keeps staring at Rio's butt, and eventually Rio finds him masturbating while looking at her butt, and he says, "I can't take it anymore!" and attacks her in an empty room...