Karin, a DNA operator from the future, is on a quest to change the course of history by preventing Junta Momonari from becoming the Mega-Playboy who fathered 100 children and contributed to the world's overpopulation. Junta, on the other hand, is not a playboy; in fact, he is allergic to girls. When Karin accidentally shoots him with the wrong DNA-altering bullet, he begins periodically transforming into the Mega-Playboy capable of seducing any lady. Karin must endeavor to return the situation to normalcy before the Mega-Playboy transformation becomes irrevocable.