[M]y kind of “cheating” with my girlfriends [f]riend

Back in october, a girl-friend of my girlfriend visited us while we were in our semester abroad in spain. We all shared one bed, with my girlfriend sleeping in the middle. Her friend wore some kind of woolen nightdress. When i woke up in the middle of the night, i had my arm around my girlfriend and was touching the side of the other girl. After realizing that she isnt noticing anything i started to "discover" her lean body (for your info, my girl is rather chubby, but her friend is very lean and slim). I began touching her back and her belly, making my way towards her legs. She has a nice and firm ass. I even was able to sneak under her panties and felt her shaved (not fresh) pubic area… remembering it gives me even now a boner. I also had the chance to grab her left boob, massaging it and making her little nipple hard. she has a nice size between a and b, in comparison with my gfs c, it felt very firm.

That's the confession part. Tonight my girl is having a sleepover with 3 of her girl-friends, also with the above mentioned girl. I am really excited about the time the fall asleep… Do you guys have any suggestions?