You'll be surprised. He might just respect women and actually be looking for a soulmate before he gets sexual. Given the fact she's experienced it all as you say, she might appreciate that innocense and actually allow her to feel innocent as well. As you say she might be OVER the partying she's done in the past. Opposites attract.
I don't agree with the whole you need to experience everything before you settle down. Infact sometimes a bit of naievity is a good thing because it doesn't make you cynical about people.
However the one thing I would REALLY worry about is that he might be gay!