Elite office lady Kurokawa Maria suddenly finds herself undergoing a bizarre transformation—developing a male organ between her legs. Quietly observing her every move is her subordinate, Ami Kurosaki. A strange triangular relationship forms between Kurokawa, Kurosaki, and Kurokawa's new penis. As the moment of full transformation arrives, the woman trembles between pain and pleasure. That single instant leads directly to the story's climax.