"But we need to come up with a third catogory"
The third category is "Charisma". You know what charisma is, don't you ? It's that ethereal, hard to describe quality....which you can't quite put your finger on.....the women with very large breasts have ( ladies, you know that's a joke ).
"What would you classify the time inbetween seeing her in person for the first time and services performed ?"
Eternity?
No, wait, that's the time period between when you orgasm and when you hear the front door slam ( yes, I know, another bad joke ).