Shy and unnoticeable since childhood, Kana has lived a plain and quiet life. Introduced by her parents, she married her husband, and their sex life existed solely for the purpose of conceiving a child—never bringing her any pleasure. Amid this monotonous existence, a vague sense of loneliness began to grow within her. One day, she was invited to a department drinking party, where she ended up having sex with a male coworker. For the first time, she experienced overwhelming pleasure and a thrilling sense of guilt. From that moment on, the intense sensation of heat filling her womb became deeply etched into her heart.