The wager

The Gotham Sirens were having a night on the town. Having hot sex with some hot but clueless men.

Harley: These men are fun but they can't compare to Batman. If only Batman were here. I wish he wasn't always escaping.

Poison Ivy: I was so close last time.

Catwoman: Oh, please. Just like the last few times.

Ivy: I'd like to see you do better.

Catwoman: I think I would. In fact, I'd like to propose a wager. Whoever makes Batman marry them 1st wins!

Harley: What would I win?