Although mother Asahi and son Taichi do not engage in penetration, they do engage in handjobs and oral sex on a daily basis. Asahi feels a sense of immorality about this relationship, but she cannot stop Taichi's requests. She is also dissatisfied with her own sexual desires, and in Kokoro she desires Taichi more than her sexless husband. As a parent and as a woman, she finds herself immersed in a forbidden relationship... she is caught in a dilemma.