Saikyou no Furyou ga Nyotai-ka! Tsundere Ore Kuchou no Bishoujo ni!?

Synopsis

Subaru was the hardest of a gang of thugs, directly descended from martial artists. How does a guy this tough end up cursed as a big-breasted woman! Feminized Subaru has to fend off perverts and find a way to return to normal. Meanwhile "her" body is subjected to nonstop erotic happenings. (Source: dlsite)