A man working for a midsize Tokyo manufacturer plans to propose to his coworker and girlfriend Miki the next day. That evening, his childhood friend Non suddenly calls, claiming she lost her wallet and needs help. He lies to Miki that he is meeting a male soccer friend, then finds the drunken Non and escorts her to a hotel room. He tries to leave immediately, but she asks him to stay just a little longer, seductively jokes that tomorrow they will both be cheating, and draws him into intoxicating creampie sex.