Daiki had always looked at Atsushi's mother, Haruka, with feelings of envy. However, one day, he discovers that Haruka and Atsushi are involved in an incestuous relationship. Shocked by the hidden truth behind the innocent facade the mother and son had maintained, Daiki is overwhelmed with deep disappointment and a sense of betrayal. His growing anger and desire for revenge begin to spiral, leading to drastic changes in his actions.