I was staying at my then girlfriends house and she shared a room with her sister. I was 20, she was 18 and her sister 19. Me and my girlfriend were in bed and made full use of having the room to ourselves as her sister was out on a night out.
It was around 2am now and I was woken as her sister came back from her night out. She noticed i was awake and looked directly at me and put her finger to her lip as if to say shhh! I smiled at her and then she began to undress slowly coming closer to me. I turned around and saw my gf was still fast asleep and turned away.
The sister now in just a green thong and matching bra about 1 meter away from me as she turned around and unclipped her bra and dropped it to the floor, before bending over and sliding her thong down over her bum and down past her thighs and until they also dropped to the floor. At this point I am feeling both extremely aroused and also like this shouldn’t be happening but couldn’t stop it and not sure I even wanted to.
Her bed next to the bed I am with just a bedside table between them. She lay down in bed and left the covers off of her so I could see all of her as she lay there and she began to play and tease her body starting with her breasts and then her pussy making eye contact with me the whole time.
She then took me by surprise when she reached over and took my hand and pulled it to her edging her self closer to the edge of the bed so that she can use my hand to tease her now wet pussy which felt incredible.
My dick at this point is now pressing hard against the duvet. She starts to wimped and placed the pillow with her other hand over her head as she starts to shake with the pleasure as she eases my index and forefinger inside her and starts to thrust gently against them.
I feel she tightens as she orgasms her hand holding the pillow down firm against her face as she moans into it. She then releases my hand and I pull it back over to my bed as she covers her self with the covers and repositions the pillow says “not a word ever and good night “
we never spoke about this again and still probably the most intense but sexual experiences I’ve had