Someone I know has borderline personality disorder

Considering the vintage of this thread, it’s entirely possible that they’re no longer together anyway. OP, you out there?

Indeed. We went on four dates and a weekend together. The deepest we got sexually was heavy petting and finding out she likes her nipples bitten. She dumped me. About 1 or 2 weeks later, I asked her questions to do a debrief of our dating to learn from it.