I discovered I had a panty fetish a few years ago and one of my sisters friends Claire was over after school and staying for a sleepover. She was very pretty and wore a very short skirt. I began to notice her panties flashing from between her legs and this gave me an instant hard on. Later that night they had gone out with mum for a pizza and being alone I wandered into my sister's room for no reason and noticed Clair's clothes scattered on the bed and something white poking out from the pile. I picked it up and it was her panties that she had been wearing, they were white cotton ones with a small butterfly on the front and the crotch had a small mark on it, when I smelled it I almost came so I undid my shorts and wrapped her panties around my throbbing shaft and pumped away until I shot a huge gob into the crotch. Afterwards and slightly panicked as to what to do with them I put them into the tumble dryer to dry my cum and slid them back to where I had found them. Although they were now dry, the crotch piece was stiff.
When I came down for breakfast the next morning Claire was already dressed and sat on the sofa watching TV. She had her feet on the edge of the sofa and her knees drawn up under he chin. When she said Hi, I almost passed out, she was so sweet but as she smiled at me I saw her part her thighs a little and flash me her panties which were white. I went stiff straight away wondering if they were the ones I had shot my load into the night before. Needing to relieve the throbbing cock in my trousers I made my excuses and went to the bathroom to brush my teeth and had a rummage through the dirty washing hamper to see if she had left her panties there. The only ones I saw were my sisters so trembling and in need of relief I picked them up, untangled them and when I looked at the crotch there was a wet sticky patch there which smelled a bit musky. It wasn't long before the crotch was riding over my hard cock and another huge spurt of cum soaking into the soft material.
From that point on I had a real fetish for girls panties including my sisters and as she got older and I knew she was masturbating at night, in the morning I would try and get the ones she had worn as they were still warm and damp with her juices. When I was older I had taken an interest in horse riding and the fact that more girls rode than boys was an added benefit. I would spend the whole day with an erection as I watched horny young girls in tight jodhpurs sit astride horses. I am not sure if girls actually get off riding but they certainly like it and watching them rocking to and fro with their thighs spread over a saddle really gets me hard. I know most girls don't wear panties underneath their joddies as they bunch up and cut into them, the thought of them walking around with no panties on underneath just adds to the fun and most of the girls have great bums.
One day to my surprise Claire turned up and now a couple of years on she was looking so sexy in her tight joddies and t shirt. She was wearing a sports bra which held her ample tits in but I could make out her hard nipples poking out. As she walked about I stared at her bum and noticed a panty line which made me stiff straight away wondering what she was wearing underneath. As it was her first time at the stables I rode out with her and a few other girls that morning and was struggling to contain my stiff cock from exploding as I watched her mount up swinging her leg over the saddle and getting a view right between her thighs, as she settled into the saddle I could make out the thick line of her panties stretched over her bum and the front of the saddle pushing right into her thighs. The whole time we rode out I stayed just behind and to her right so I could watch her perfect bum rocking to and fro, a few times she stood up in her stirrups and her panties were cutting a tight line over her bum.
As we rode on she began to look uncomfortable and was shifting about and I was guessing her panties were bunching up and rubbing her. After about an hour we returned to the stables to prep for the afternoon and this time when Claire appeared I noticed her panty line had gone, she'd taken them off and now her joddies emphasised her cute bum and sucked slightly into her lips at the front. Just before she joined the rest of the girls she held out her hand and asked me if I could hold onto something. I held out my hand and almost passed out when I felt her place her warm panties in my hand, with that she smiled and trotted off. When they had gone I went to the toilet and released my straining cock from my pants and opened my hand. There in my palm were Claires white panties, so soft and warm and quite small. When I checked the crotch it was soaked in her juice and still sticky. Being embarrassed and excited at the same time I realised she sussed me out a couple of years ago. I was in heaven as I stretched the panties out onto the toilet seat staring at them as I wacked off. They must have ridden right into her slit during the morning ride and rubbed her pussy beneath the tight joddies. Then I picked them up and placed the crotch piece over the end of my cock and rubbed away until I shot my load into the soft fabric, remembering how it had felt almost two years ago. I managed another two orgasms with her panties before she returned and just as Claire was about to leave I gave her the wet panties back, she smiled at me and walked off, what a day!