It was last summer. I was (and still am) 19. A friend of a friend was visiting, and the three of us went on a picnic the night she arrived, and there was lots of joking and lulz to be had, including a humurous discussion about using reverse psychology to get sex. I took her hand and said "Martine. I don't want to have sex with you. I'm sorry, I know how much you want it, but I don't." and then everyone laughed. It was p/funny.
Anyway the next day we spent the day outside eatting jam and bread in the sun and got horrible sunburns. In the evening I went and hung out with someone else entirely who went all motherly like and said "you have a sunburn!! YOU MUST TAKE THIS ALOE LEAF" so I did and I had some aloe then.
Then later just before I was about to go to bed and was naked under my bathrobe and there was a knocking on my door and it was her. So we sat and chatted (I was still naked under my bathrobe) for several hours, gradually moving closer to eachother on my bed. Also, at this point I thought she was a lesbian since she talked about her recent 3 year relationship with another woman. Anyway, we noted eachothers sunburns and I was like "hey I got some aloe why don't we use it" so she took off her shirt (no bra underneath) and I thought "oh she's just really comfortable with herself. She's a lesbian so this doesn't mean anything" and I rubbed aloe all over her body. Then she put my hand on her boob and I thought "oh, this is just platonic. She's a lesbian so it can't be sexual". Then she noticed my erect penis and grabbed it, and that was when I started to get suspicious. Then we did it. The end.