I think just flattening the hip curve on the right side should help. And perhaps on the left too, below the butt. The butt itself is fine; it's a common mistake to try to make men more "manly" by not giving them butts, but guys have butt fat too.

Yeah, I've drawn women almost exclusively for the past 3 years or so, so it's tough to get androgynous dudes just right without going too far into "girl" territory.

I didn't realize this was intended to be a boy (and even wondered what the name had to do with the piece) until I read your description. I don't think that's a problem, but if your goal is to have the character clearly read as a male, you may want to reduce the difference in width between the waist and hips, since he's quite shapely currently. There are also other subtle things you may be able to do, should you want to.