My big sister is that kind of girl that can't say no to a hard dick but now she's in a relationship with a guy she really loves and she's completely scared the guy founds out she's fucking around. I think she's a nynphomaniac but she says she has problems with commitment and when she gets too involved she unconsciously does everything to get out of the relationship. I get into the picture because she's trying really hard to keep the guy she has, in her mind with her brother it doesn't count. Yes, I know it's weird maybe that's why she goes to a shrink.