Funny you should say that, since I only found it because someone on 4chan said almost exactly the same thing. The story's really not my cup of tea, but Cruz has been enough to string me along up to the latest chapters.
I can't believe I forgot about Hourou Musuko! http://mangafox.me/manga/hourou_musuko/
I really liked the early chapters, but I feel like it's gotten bogged down lately. Kind of sad…
Anyway, thanks to everyone for the nice comics! I really like this kind of stuff, though I do wish there were more crossdressing stories with a serious bent.