Kenji, a humble office worker with erectile dysfunction, had a cold relationship with his wife Mao. One day, he bumps into Nakata, who lives next door, at the park, but learns that Nakata is unemployed and has been kicked out by his family. Kenji invites Nakata over for dinner with his wife, but seeing Nakata attracted to the beautiful Mao, he begins to feel a desire to cuckold her...