Crazy ass lighting. It's in the places where there should be shade.

Well not necessarily. Seems the artist was experimenting with refraction and diffuse reflection effects. Not to say the result is totally convincing.
Have to hand it to him though, he's really got that perfect sphere thing down pat on her right ass-cheek. Seems only that strip of cloth keeps it from popping right out of the screen, corona and all. ;)

Not necessarily? This is physically impossible. Butt creases do not shine.

You need to stop being so abrasive.

What does 'abrasive' mean?