My sister was on the swim team in Jr. College. She looked so hot in her bathing suit. She is 19, 5'5 125 lbs. with green eyes and dirty blond hair. She had big boobs too. She was a double d cup. I am 18 6'3 150lbs brown hair green eyes. She would always walk around the house before her practice and meets in her bathing suit. Every time I saw her in her bathing suit I would get hard. I would always try to sneak pictures of her when she would lay out in the back yard tanning.
She would leave her bathing suits in our bathroom to dry. After every meet or practice I would sneak in and stroke myself and cum in the crotch of her bathing suit. She had no clue I was doing this. One day she took her suit off and put it in the bathroom. I sneak in and came in the crotch. Right after that she went back in and put it on again to go lay out. It was still damp from the pool so she did not notice the crotch being wet. I went to my room and jacked off knowing my cum was rubbing on her pussy.
Our dirty close hamper was in the bathroom as well. She would leave her bras in there and I would cum in them as well. By the time she picked them up they were dry. One day she left her bra in the bathroom by accident and I came inside of it. When I left and went to my room I saw her go in the bathroom after me. When I went for dinner, my sister was wearing a tank top and I could see the color of her bra. It was the one I came into. I wondered if she knew. She never once even gave a hint that she knew.