His mother, Aki, is deeply frustrated. Lately, she can't stop masturbating, even when he's in the next room. Hearing her sad moans, the son is heartbroken and decides to do something forbidden to show his filial piety. He wants to comfort his beloved mother. With that thought in mind, he forces himself on her... The two of them instinctively clash with each other's love and lust, crossing the forbidden line. Their intense feelings can't be calmed in one go...