It's present in a lot of anti-aging creams. The before/afters are sometimes incredible.
I think it could especially help to feminize a face!
You basically start off slow, applying just a little bit once every three nights for a week, then every 2 nights for a week, and then finally every night et al. It makes the skin much more sensitive to sunlight as it inhibits melanin production, but this also means that it evens out skin tone. It takes a few weeks for skin to adjust, at first it peels quite a lot.
Seriously though, the skin on my upper lip is now BABY smooth. I'm going to get some of the straight up retin-a cream (not as part of a bleaching cream) and use it on my whole face.
It does build new collagen, and the collagen lasts. It does wonders to keep your skin young and healthy.