Happened a few years ago
During my first year of high school I was dating a girl we'll call Jess. She was pretty toned and had nicely shaped tits. Being my first girlfriend and being at a very sexually active age, we did all sorts of things as often as we could, in school, outside, at the theater, anywhere.
So one day I was sleeping over at her house, and just being her and her mom living there we were technically on our own, which was great for us. We got to our usual business of stripping naked and having some fun though unfortunately that was cut short due to her mom having dinner ready for us. So we went downstairs for dinner and hung out with her mom for a bit before saying goodnight and heading back upstairs. After we got back up we went right back to being naked in our own little section of the house. Jess started off by slowly feeling my balls as I felt her tits and ass. She started to feel my cock as it grew and got harder by the second. She pushed me down on her bed and knelt down, my cock inches from her face. She started to stroke me faster and faster as she watched my cock get harder and harder. I was moaning a bit as I could feel myself getting ready to cum, and Jess kept saying 'cum on me cum on me' I was ready to burst when I heard a creak from just outside the room. The door opened and her mom entered, wearing a robe. She was shocked, couldn't believe the sight she was seeing. I immediately tried to cover myself, and Jess just froze in place. 'Oh my God' her mom managed to get out. I was shaking from being so nervous. Her mom turned and left in a hurry. I couldn't move, but Jess turned to me and said 'I'll be right back'
I stayed there for what felt like an hour but was probably only minutes before Jess came back in the room, still fully naked. In the time she was gone I slipped some pants on. She sat beside me and put a hand on my knee. 'What happened?' I asked. She just said everything was ok, and started to feel my cock through my pants. I asked if it was a smart idea to keep going, but she said I should go and apologize to her mom first. I thought it was crazy and especially being hard again was not interested in that idea at all. After a bit of forcing I got up and headed out of the room, with Jess saying she'd be naked and waiting.
I stood outside her moms room for a minute before knocking lightly. I heard a light 'come in' and opened the door, seeing Jess' mom sitting on the edge of her bed. I walked over to her, heart pounding and I said sorry for what she saw. she said she knew that we do stuff like that but to always stay safe. I thought she would be freakin out more but she seemed to be understanding, maybe it was the single parent aspect. I started to say again that I was sorry before she cut me off with something I'll never forget. 'you know being a single parent doesn't leave much room for a love life, and I miss having someone' I didn't know what to say. I just stood there. She continued with, 'you know Jess and I have a very special relationship. We often masturbate with each other' my dick got hard instantly. 'Oh uhhh' was all I could say. 'Is that something you would be interested in?' She smiled at me and looked down at my pants, a huge bulge. I just stood there, I don't remember if I even nodded, but her hand stretched out and lightly touched me. 'Jess!!' She called out, and Jess was in the room, naked. She came beside me and said 'you ok?' I nodded. Her mom stood and removed her robe revealing large boobs with a slight sag, a fit body and a trimmed pussy, and Jess slid down my pants. Now we were all naked. More to come.