Once you get up there in lvls she's not nearly that hard. Check your Analysis skill (which you should buy at the very first chance you can, if you haven't already), iirc she's vuln to Seduction attks. If you've got decent escaping skills/stats, and spam her @$$ w/ Seduction attks, she's kind of a pushover.
One thing about this game that I LOVE, because it's so realistic, is that you HAVE to change up your attks constantly, even if it's only rotating thru two or three different ones (even from the same menu, like Seduction or Mouth) on any one girl. One of the most basic cardinal rules of fighting is NEVER do the same attk more than twice in a row.