Morrigan Aensland's Bloodlust
Because sometimes you just want to get with a girl who's scary as hell. You certainly wouldn't bring her home to mom (is that notion antiquated yet?), but you might take her for a romp in the interdimensional hay. In the case of Morrigan, especially, that romp might be your last, but it would probably be worth it.
We're not saying our perfect girl would have all the properties of a demonic succubus vampire, but she'd definitely have a wild side. Not the kind with wings, but you get our meaning, right?