I'm still surprised sometimes by just how unbeatable you've made the character of Kat. From all that has been said and shown it seems she is a true loner; she is someone who does not need others. I imagine she could be locked in a concrete box in a foreign country for months and not suffer the loss of company, happily clacking away with knitting needles and humming a tune.
On the other side, however, she can still interact with people and would still seek them out, making her able to have relationships for as long as she wanted. She just doesn't seem capable of being lonely.
That was a nice shocking reveal for the sexual attraction aspect
I'd say it's not surprising but it only isn't in retrospect. Everything she does is a little unexpected because she is a hard character to predict or understand.
I also take back what I said about her being a villain. Kat is more of a dynamic character that cannot be labeled as 'bad', at least as I see it.