Like most of these things, it just happened.
I had broken up with my first serious boyfriend. Finding him in bed with someone at a party was awful, but in one way, it made it easier to dump him. We hadn't been getting on too well lately anyway.
I walked home from the party and was feeling a whole range of things. I was angry as all hell, and also felt rejected because he obviously preferred her to me. But then I also felt very lonely too. By the time I got home I was in quite a state and I ran up to my bedroom.
Soon I was having a full on cry and feeling like shit. I didn't hear my door open, but the next thing I knew my big brother was sitting on my bed holding me as I cried. I just let it all out and he just held me tight and rocked me gently. As I calmed down, I kissed him, and, er., not a brother/sister peck either. I gave him a full on open mouth, well, everything. Thing is, he didn't move or pull away. So I snogged him and I took his hand and put it between my legs. Somehow, with all the crying and all, I had gotten really aroused. I pressed his fingers against my wet knickers and he took the hint and started to rub me. Then he slipped his fingers under the material and inside me. It was heaven! I breathed into his mouth "Oh Mike, please, don't stop. For fucks sake, don't stop." He tugged my knickers right over to one side and fingered me really deeply and diddled my clit with his thumb too. The next thing I was cumming hard onto his fingers. I must have looked a right state sitting up on my bed, my knees wide apart and with my brother's fingers inside me, but it felt wonderful.
As I came down I reached for him and boy was he hard! I unzipped him and he said something like "Sara, you don't have to." But I wanted to. I jacked him gently at first then faster and faster. Then he said "Oh Sara. I'm gonna cum" and I just kept going. He blew his load all over the crotch of my knickers. And there was a huge amount of it too. Then he left. I lay in bed with my sperm covered knickers still on and masturbated again. I even tasted some of it and pushed some inside me. I felt really dirty, but it was hot as hell too.
I guess I really needed it.