Reijin ni kanpai (1983)

An 18-year-old boy who came from the countryside to attend school. The person he was introduced to to share a room with by a real estate agent was a man who looked like a girl. He joined the boxing club because he wanted to be more manly, and even he (his girlfriend?) found it interesting and decided to join the club as its manager. The club members are overjoyed at the appearance of their cute manager, but the boy who knows the secret is complicated.