I, personally have an issue with feet.
Not so much that I find the actual anatomy of them difficult~
Just because feet kind of freak me out a bit, so I'll do just about
anything to avoid drawing them.
Which means a lack of practice, and through that,
a lack of skill. = = ;;
The curving of the spine is also a bit difficult, just because it's hard to get a gentle and appealing curve without it looking as though they are forcing thier body forward at an awkward angle.
XD