Kana has been shy since she was a child, with a low presence, and has lived a quiet life. She married the man introduced to her by her parents, but she has never experienced orgasm through routine sex for the sake of having children. One day, while feeling vague loneliness about her life ending without incident, she was invited to a drinking party with her department and ended up having a relationship with a male colleague... She experienced pleasure and feelings of immorality that she had never experienced before. Since that day, Kana has not been able to forget the feeling of a hot liquid pouring into her uterus...