There is one obvious betrayer. There is a hint that it might not be his/her fault tho. There might be two, I'm about to find out. Almost done, apparently. May I add the path finding is ridiculously bad in the area I'm currently in
However, the person I killed gives you his/her equipment before leaving (if you fail a influence check, and I never used him/her). As an evil character, I wasn't about to allow them to leave me like that, and I wasn't going to miss a chance to do something actually evil for once.
EDIT: Is there actually romances in this game. I never really pursued them, but Im curious if they exist