Apart from the fact that it's physically impossible for Harley's leotard to be so tight that it shows each breast's individual shape and allows them to hang like that... this is an amazing piece of work.
I think this is a very well done sketch, overall. Your penciling is excellent and it's hard not to laugh at Bat-Mite down there looking like he's hit the jackpot. but what I can't ignore are Harley's breasts. I'm not going to complain about the shape; exaggeration is part of comics, but unless her costume is literally painted on, there should be some indication that the breasts are stretching the fabric of her costume as opposed to the clothing mapping to her body like a 3d model. To be honest Ivy's breasts don't bother me. I've seen skinny girls with large breasts, and her costume, as it were, isn't as distracting.