Well, its good that you warned both of them. She seems like a nice girl and I would feel terrible if your friend just wanted her for sex only. Thats crazy.
But, yeah, if he truly wants to be with her other then the sake of sex only, then I would say go for it. Or you go for it if he's that dumb.
I took an extra semester in Highschool after I graduated, and I met this guy that was 22 and had already graduated college, etc. We both ended up going out and it was a great experience for me. Sometimes it can work out, you never know unless you try. Its one of those life lesson things I think.
I agree with Shille, girls tend to mature faster then guys. Depends on the girl too. I act like I'm in my 20's, but I'm still 18. Most guys are amazed that I'm so mature for my age.
Anyways, Good Luck!
PS: Sorry if I was a little rude about your friend above. I just get so annoyed with guys that try to take advantage of a girl.
Evil School!!
May not be on LF as much, due to unforeseen circumstances.
Blame College and Homework for Everything!!
-Fawn