Once I accidently saw my step-sis - pretty, slender, brunette Haven Rae - enjoying hot sex with her bestie - slim, small-titted, blonde Sydney Cole. I was shocked 'cause I didn't know that she was a lezzie. She noticed me watching them and I ran away. Yet, on the next day she came up to me and told me that she wanted to share my cock with Sydney in threesome and, despite my rather conservative views on the the subject, she managed to talk me into this madness.