I (M20) started living with a friend (F19).
It was a really small room for both of us, and after a few weeks, she got home while i was jerking off in the bathroom - door was closed, but it wasn't that hard to notice.
So after that she went to talk to me, and we agreed to just do in in our beds whenever we wanted.
I absolutely loved the ideia, i would ramdomly get to see her pussy while she touched herself, and obviously, i started jerking off every time.
We started to basically masturbate looking at each other every time, and it was so good.
One day, when i got home and saw her naked and getting started, i decided to jerk off while standing, with my cock close to her face.
She just started sucking immediately, and after that, we started to have sex constantly, until we eventually started dating.