My controlling girlfriend will not even let me masturbate to another woman. Hoping to make her break up with me, I ask to film her having sex with my friend as jerk-off material, but she unexpectedly agrees. She hesitates when filming begins, then gets far more excited than she ever does with me and cums repeatedly with a filthy expression I have never seen before. The sight makes me rock hard and suddenly wonder whether dumping her would be a waste.