[Blarg]

Alcohol gives girls an excuse for doing what they really want to do anyway. Which is have sex a lot more than you might think it is. Sometimes even with you specifically. Or at least you'll do for the evening. It provides deniability on a level deeper than the lack of inhibition alcohol gets you. This is vital to the psychological comfort of a lot of girls, who aren't as comfortable yet with the idea of expressing their sexuality yet as their hormones are. They're just as horny as you, but sometimes those inhibitions roadblock them, especially if they're around their friends, where they can become very subconscious -- and status conscious, if only to please their friends. Who would often be just as happy if she didn't get laid at all, if they're not getting some.

Booze is a handy excuse for girls to do what they want to do. Don't stand in their way. Provide it, but with caution. You don't need her barfing on you.