My sister and I are 3 years apart. We shared and laundry basket so I would see everything she puts in it. In high school, I noticed she started to change the style of panties she would wear. It went from regular cotton panties to silk bikini smaller panties. Around this time, all of the girls started to wear thongs, even the younger girls my age (i was 14, my sister was 17). I would always dig through the hamper to see if there was finally a thong, but nothing. Towards the middle of her senior year, I was digging through the wash and couldn't believe it! It was a super tiny tan thong folded up in her jeans! It got me so horny I jerked off into it and smelled it immediately. I always got home from school about an hour before my sister, so I had plenty of time to play. Parents were at work. This was her only thong for about a month, then out of no where all thongs and G-Strings! All I would think about all day at school was getting home to jerk with her thongs! I would always cum in her thongs and leave them out of place so she knew I was jerking with them. I dont know why, but it turned me on!! Im pretty sure she knew because she started leaving her thongs on top of the wash after she would shower. At night, I would go to the laundry when everyone was sleeping and jerk again. Never failed, she always kept a thong right on top of the wash and I would always put them under her clothes after I would jerk. She knew for sure! Before she would always have her thongs tucked inside of her clothes. She would shower at night so thongs were always fresh. My sister is 5'2, petite body, about 115 pounds, brunette. We are in our late 20's now and both have our own places, she is still a thong wearer but I haven't played with hers in a while.