It might have been suggested when Holly lingering so close to her. "It's what you wanted, isn't it [Gotham's destruction]?" [Selina shakes her head]. Interestingly, Holly reminded me of a cat in that instant as felines like to rub on other people for attention. Considering that Selina didn't own cats in the movie, that might explain why Holly adopted cat-like behavior. I'm just rambling, I don't mean to sound nitpicky. I loved Catwoman's portrayal in TDKR.