Slightly sadistic Shou and masochistic Riko were a good couple because their sexual preferences matched each other. One day, they planned to invite Shou's friend to introduce him to Riko's best friend, Aki, but Shou's friend couldn't participate at the last minute, so they had to gather around the pot with three people. Aki, who was asked to buy alcohol, accidentally witnessed Shou and Riko having sex. Shou felt awkward after being caught peeking at his ejaculation, and Riko didn't know anything. While Riko was already drunk and fell asleep at the party, the mischievous Aki began to torment Shou's nipples...
