Can someone explain why her thumb looks like it's undergoing mitosis?
I'd assume the artist tried to make the thumbs looks like they're crossed each other in / \ position, but due to the space constraint of her breast they made a (bad) choice of drawing both instead of only her right arm's. The left arm's one should be completely obscured from view anyway, given the relative length of her fingers compared to the boobs covering it.
In other words, too much attention to detail actually ruining the picture.