Mayu, a wife, happens to meet her husband's friend, Kayama. He is friendly and has many hobbies, so she opens Kokoro to him. But one day, Kayama comes on to her and she is unable to resist, leading to a physical relationship. She feels guilty for being carried away by his lonely expression, but... It's been a long time since she's had a relationship with her husband, and Kokoro down inside her body she secretly desires to be violated by Kayama. Then, at her husband's request, she has no choice but to visit his house...