Buddy!!!

Ryuudo Kagetora, a tall student determined to become Japan's top basketball player, enrolls at a once-renowned basketball high school with the goal of restoring its former success. He harbors a strong dislike for girls after being defeated by one in a basketball game during elementary school. Joining the team is Ichinomiya Chiaki, another talented new player who previously starred on the middle school girls' basketball team. Chiaki transforms into a man while playing basketball and was expelled from the girls' team when this ability was discovered. Ryuudo discovers Chiaki's secret and, despite his reservations, agrees to support her and becomes her roommate.