I (27M) watched my lesbian roommate (25F) fuck a tinder hookup (25F)

Obligatory this happened a year or two ago. I still have the same roommate. We've been friends for years, and she's a lesbian. One day, I was sitting in my room playing some game on my computer when I started to barely hear the sound of moaning over my headphones. I pause my game and take my headset off to hear the clearly audible sound of a woman in the throws of pleasure. I get up from my computer and wander into the hall fully intending to go to the kitchen for a snack and also get a better listen to what's going on, when to my surprise I see her bedroom door is wide open. I quietly step down the hall to her door and listen from around the door frame. The sounds of pleasure are loud and clear. I peek around the door frame and see my roommate laying in her bed, naked, legs spread, tits out, with another girl's face between her legs. Instantly I'm rock hard, I watch from around the door frame for a second before this sense of "fuck it" comes over me and I just step out into the door and just start openly watching. My roommate looks up and makes eye contact with me for a moment. Her fingers are entangled in the other girls hair, and she doesn't even pause her moans. We lock eyes for a second and then her eyes go back to watching the girl who's tongue is working on her pussy. Taking this as an invitation to stay and watch, I do exactly that. Standing openly in the doorway, I watch my roommate get brought to a loud, full body quivering orgasm on this girl's tongue. As soon as my roommate is done Cumming I quietly wander back up the hall to my room.

Not three minutes later, I hear the sound of skin on skin slapping together and another female voice rising in pleasure. I quietly wander back down the hall and peak around the door frame again. This time, I see my roommate standing next to her bed with a big purple dildo strapped around her waste. The girl is in the doggy position on the bed facing away from me at about a 45° angle. And she's getting her brains fucked out by my roommate. My roommate looks over at the door again and seeing me standing there, she smiles and angles herself slightly away from the girl she's fucking, and slows down her thrusts, giving me a clear view of her big purple dildo disappearing into this girl's pussy. At this point, I can't resist. I pull my dick out and start jerking off right in the hall way, my roommate gives me the show of a few slow thrusts before repositioning herself and returning to the rapid deep thrusts she was giving when I first walked up. I watch this girl get brought to a full body shaking orgasm and her legs give out as she collapses down onto the bed in orgasm. My roommate gives her no respite and continues to deeply penitrate her pussy for several more minutes in the prone position before pulling out and revealing the purple dildo dripping in the girl's cream. I quietly wander down the hall to the bathroom, where I finish myself off.

Later on that day, I was properly introduced to this girl and found out my roommate insisted on keeping the door open. Since the girl was just here for a hookup, she just figured it was some type of kink and went along with it. She knew I was home when they got started. My roommate and this girl and i took things further on a few occasions after this if that's something anyone would be interested in reading.