I was incredibly surprised at the quality of the game "Wanda the Pink Horse" which is probably not an accurate translation of the title. It's a Wonder Momo side scroller:

http://www.dlsite.com/maniax/work/=/.../RJ082148.html

Note that it does have incredibly minor nudity when she comes out of her transformation. Some of the voice clips get annoying, but other than that it's a really fun game. The same creator also made a couple of brawlers starring Tifa with a bit more nudity to them that are also pretty decent games.