The Exploding Girl

After witnessing a girl who is exposed to bullying, the guy takes a step to stand up for her.
However after getting beaten, he attracts the attention of a strange talking rabbit and tells the guy about a contract with him where he can get the power to defend the girl. Here, he's given his transformation, but not with his own gender.
What will this lead him to...

The story of a guy who turned into a cruel girl with strange abilities.