I've been with my gf for 4 years & she considers herself to have a low libido. I'm a sex addict so I want to have sex all the time; I'm into almost everything threesome, S&M, RP whatever but she isn't. She said she enjoys Role playing & Bondage but not alot. After sex she told me that she loves to watch me masturbate & it really turns her on she also told me that she wants to hump my ass??? She said she never thought about humping a guy's ass before but she always loved men's butts. Needless to say I was shocked. So any idea why she wants to masturbate or hump my ass obviously it turns her own but any idea why?