When I was growing up I was curious about everything. But we lived in the countryside and this meant my curiosity about sex was difficult to satisfy.

As I turned 16 I started to have doubts around my sexuality and was very confused around whether I was straight or gay. That year I was in the college pantomime and was cast as one of the ugly sisters. It was my first experience of cross dressing. As part of the script I had to lift up the dress I was wearing to flash some very old fashioned frilly knickers. The problem was that I really enjoyed wearing those knickers and sometimes I got sexually aroused when wearing them. A few times I even managed to sneak to the toilets to masturbate myself whilst wearing them.

At the time this meant I started to think that I might be a cross-dresser or maybe a transvestite. But I certainly knew that I enjoyed being dressed in women's clothes.

As the weeks passed after the pantomime I grew more and more desperate to get that same level of erotic thrill that the cross dressing had given me. I hatched a plan, my parents often worked late and my 17 year old sister Mandy was often round her friend’s house. When they were all out I would sneak into my sister’s room and dress up in some of her underwear.

The first time I did this was one winter's evening. I crept into Mandy's room already half aroused by the thrill of sneaking around. I looked through each drawer in her chest of drawers. I quickly found what I was looking for. As I looked in her underwear drawer I was surprised to find that she had some sexy underwear. I was only expecting to find some plain cotton panties, but I found several much sexier sets of lingerie. I quickly stripped off. I was stood naked in her room with my cock rock hard.

I pulled out a pair of small silky panties and a matching bra. The set was black with frilly edging. I put on the bra and then slipped on the panties. The tiny silky panties struggled to contain my erect penis. I started to rub myself through the panties and ended up getting onto my sister's bed. I lay down and frantically rubbed myself through the panties. Before long I was masturbating myself very hard and fast through the panties. I took long hard strokes of my erect cock. Before long I was running into the bathroom and letting my cock explode big sticky splodges into the sink. I tidied up the mess and put the underwear back away. 

Having gotten away with it once, I got more and more adventurous over the next few months. I ended having some amazing orgasms in various states of cross-dress. Over time I tried different lingerie including Basques, baby dolls and my favourite stockings and suspenders. I even refined my plan and when time was tight used a condom to avoid the dash to the bathroom.

After a while I decided to go further and fully cross dress. The first time I tried it I got very excited. I picked a partially short skirt, stockings, suspenders, thong, matching bra and tight top. When I was dressed I borrowed some lipstick and finished the image with sexy vibrant red lips. Before long I had the skirt hitched up and was masturbating my erect cock. I was so turned on it didn't take me long to cum. I took the top and skirt off and started to put them away. At that point I heard the front door open and I started to panic.

I quickly finished putting the skirt and top away. I tried to take one of the stockings off but in my panic I slipped over. My sister walked into her room and saw me on the floor. I was laid out with one of her sexy bras on, matching thong, suspenders and one stocking the other was on the floor.

To make matters worse the thong hadn't contained my penis and my semi erect cock was sticking out of her thong.

Mandy took one look at me, started to laugh and said "Well what do we have here?”

She went on to say that she had noticed that her underwear wasn't always quite how she left it and she had guessed that I had been borrowing it. She had, however, thought I was just using it to masturbate with and hadn't thought that I might be wearing it.

Then she said that I would have to pay a price for using her underwear. Removing her coat, she then slowly undid her blouse and slipped that off. Next she took off her trousers and she was stood over me wearing just a red bra and matching panties. She ordered me to pleasure her as I had taken pleasure from her clothes and made it very clear I needed to make her cum and quickly or she was going to make a whole lot of trouble for me. I reached forward and started to rub her through her panties.

She lay on the bed and told me she liked to be tongued. So I gently moved her panties to one side and run my tongue along her pussy lips. She moaned how much she liked that and told me to finger her pussy. I probed her pussy with my index finger, inserting it gently at first and then harder as she groaned for more. This went on for 20 minutes or so before we stopped as we knew our parents would soon be back. She told me to keep the underwear for now, and that I would need them in the future when I would finish paying her back.

A few weeks later I came in from college and went to my room. On the bed was a note telling me to put on the underwear and come to her room now. Next to the note was a condom. I quickly stripped and slipped into the thong, bra, stockings and suspenders. I picked up the condom and went to her room. I gently knocked on the door and she told me to come in.

When I went in she was laid on the bed wearing a very sexy black Basque with stockings attached. She had a vibrator next to her on the bed which she had obviously been using it. She looked stunning and incredibly sexy. She told me that I knew what to do. So I bent over her and started to rub her pussy through her panties. Next I slipped her panties down her legs a little so that I could get to her pussy. My tongue was a blur as I licked her pussy lips; her sweet pussy was already wet. Before long she asked for the vibrator and so I picked it up switched it on and pushed it deep inside of her.

She gasped as the vibrator went deep inside of her. I could see little beads of sweat running down her neck into her breasts. I used the vibrator on her for long enough that her pussy was soaking wet and the vibrator was slipping in and out easily. She then told me it was time to fuck her. I knew I shouldn't but I was too turned on to resist. I got the condom package opened it and tried to put it on. I was so nervous I couldn't get it on. Mandy reached over took it off me and slipped it onto my erect cock. Now fuck me she ordered. I didn't need telling again. I jumped on top of her and roughly pushed my cock straight into her. I immediately start thrusting deep and hard into her. She let out little gasps and moans as I fucked her. Her hands ran up and down my legs still in the stockings. As a horny teenager I didn't manage to hold it for more than a few minutes and so let my load go.

Mandy let out a little moan and then told me we were done for now and so I left and cleaned myself up. This wasn't the only time we had sex but it was the time that I often turn my mind to and I always end up masturbating myself at the memory.