Furyou Shounen Nyotaika ~Ijimekko wa Choukyou Shiteshimae!~

The protagonist, Kyou, attends a school for boys where his appearance often gets mistaken for that of a girl. Despite this, he is the leader of a delinquent group and engages in various misdeeds. At home, he masquerades as a "nekama" (a male player pretending to be a female) in an online game, deceiving and mocking other players. One day, Kyou steals a can of juice from Nakano, who is a target of bullying, and drinks it all. As a result, his body starts undergoing changes. Kyou's appearance gradually transforms into that of a girl as time goes by. While keeping this a secret, Kyou continues to behave as usual at school and live his everyday life. However... ...Everything changes when Nakano presents a photograph that alters Kyou's school life. [dlsite]