Japan is facing a significant problem of overpopulation in the forthcoming days, all due to an infamous womanizer named Junta Monamari, also known as the "Mega-Playboy." Reports disclose that Junta has fathered children with over a hundred women, and his offspring have inherited the Mega-Playboy gene, leading to an uncontrollable situation.
To avert this impending crisis, Karin Aoi, a skilled "DNA Operator," is sent back in time to modify Junta's DNA composition and deter him from turning into the Mega-Playboy. The only way to achieve this is by shooting him with a specially-designed DCM bullet containing a chemical that can suppress the gene. In return for her services, Karin is promised a substantial amount of money, which would help her realize her dreams. The question remains: Can Karin steer Junta towards a better path, or is he destined to remain a playboy? Furthermore, she finds herself falling for the authentic Junta and Ami, a kind-hearted girl who has always had feelings for him. The future of Japan is at stake.
