In Lae'zel's terms, think of it in the more mercenary sense - it isn't about *you* at all. From her perspective I view it as more a case of:
"Well, I'm here now and I'm travelling with this lot, and damnit, I'm stressed and in a mood to celebrate and I want some [insert anatomical preference here]. I'm sure as hell not waiting until I find a creche where my superiors will be the ones holding the reins... Who in this lot of slave-fodder material-plane mud-dwelling savages can I use to suit my needs? That one? That one. You, yes you, physically capable flesh being, service me."