Hello!
First and foremost your best bet is to always contact an administrator, or simply just rate for safety. For instance, if you think your story could scrape by as a T, then you probably should rate as an M.
But as far as your description goes, I think M would be what you're looking for, if it's a matter of sexual... areas, but not sexual
content. I myself would hardly consider it MA if it was a scene description, say, Kagome's breast examination because she might have cancer. MA is for actual descriptions of sexual situations, strong violence, swear/cursing, etc. But if you get into lengthy detail about touchy subjects, sexual or not, MA is probably the safest bet. Just keep in mind that everyone has their own views of what appropriate is. So even is 99% of the site believed it to be T, if an admin says M it's M. I am not an admin, so my opinion isn't anything solid to use, it's just an opinion.
For what it's worth our admins are really great and you should get a response very, VERY fast.