Ninkyou Tensei Story
An old school yakuza, Nagamasa Ryumatsu, ended up losing his life due to certain circumstances. But, when he awakened to a strange sort of scenery he had never seen before, he found that he had somehow changed into a beautiful girl!?
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Q: Is this the official site for Ninkyou Tensei?
A: No, The entire site is fan-made.