Your story about caravan holidays reminds me of a situation many years ago.
In my late teens I was with a gf (Amy) and her friends' parents owned a static caravan in Wales.
So one unusually hot British summer her friend and bf and me and Amy arranged a week away together.

I drove me and Amy and the others, who I hadn't met apart from a brief evening making arrangements with the other girl, drove in her car.
We met and as it was her parents caravan, her and bf took the double bedroom and me and Amy had the smaller two single bed room.
We got to know eachother and it went well sharing meals out and drinking sessions late into the nights.
The weather being so hot and sunny meant we spent most of the days just relaxing either at a local beach or outside the caravan.
One sunny afternoon the other girl ( can't recall her name) was away having some beauty treatment which left me with Amy and the other lad at the caravan. We made plans for a barbeque and as it was my turn to pay for food I said I would drive to a supermarket and get supplies. Amy decided to stay in the sun.

I left in my car and was nearly out of the caravan site when I realised I had stupidly left my wallet in our bedroom.
Instead of driving back, the site layout meant I could leave the car and walk down a short pathway to where our caravan was sited
A few seconds later I was approaching our caravan from the rear and to the side opposite where the doors opened.
For some reason I glanced into the window of the double bedroom and saw (lets call him Sam) in silhouette standing in his bedroom doorway looking out through the open caravan door and beyond to where I saw Amy's torso and legs ( no head showing from our view) on a sun lounger. I quickly realised he was just standing and staring at her fit and slim tanned body lying in a bikini knowing she could any second get up and realise what he was doing.
I was intriged and a little excited , even more surprised when, just wearing shorts, he half slid them down revealing (to me) his butt crack as he must have slowly started to wank his cock while staring at Amy's body.
Fuck, should I say something and break up this scene or what.? Instead I felt my cock have a little twitch at the thought another boy was finding my gf hot enough to have a (danger) wank withing a few feet of where she was.

His wank movements meant his shorts gradually slid below his bum ( my view)and I noticed how it tensed with each stroke. I was not in any way excited by his body but what it was he was needing to do over a sexy girl who happened to be my gf. Quite suddenly he stopped and pulled up his shorts and disappeared into the caravan. I thought he may have had enough of the risk or even cum. Instead I noticed some movement/shadow in our bedroom. Ducking back out of view I was not seen when he re-entered his bedroom closing the door behind him and the direct view of Amy.
He laid down on his back within a few feet of me outside and I made sure my angle of view did not put me at risk of being seen and I hardly moved as I amazingly saw he had a pair of girls panties ( later proven to be a used pair from Amy's wash bag) in his hand which he wrapped around his hard cock as he carried on with his wank oblivious to me outside .
By this time I was nursing a semi myself, the sensibility of somehow stopping the whole thing had left me and my hornyness took over as I watched and listened as he played. stroked and moaned quietly until his movements sped up and he shot a load of hot cum over his hand, tum and dribbled onto Amy's panties.

Realising my own risk at this point I quietly walked off to my car and drove back pretending I'd got to the shops before realising I had left my wallet. Amy was still outside sunbathing and Sam was moving around in the caravan getting the barbeque set up, so all was as if what I had seen hadn't happened.
I collected my wallet but before leaving again , checked Amy's wash bag....and yes you all know what I discovered in there ....and sticky !)

So not a story about my danger wanks ( of which I will think back and maybe post sometime) but another lad who must have enjoyed what he did , all fuelled by my pretty half naked gf very close by.
As an aside, all of us split with our partners withing 3 months of the holiday but remained in touch ( there may be more to retell, but I shall leave that for another time as I have to get some work done!)
I wonder how many other times he did or had done that or indeed any others of us?

I apologise about the length of my tale , but as I was typing I indeed was getting more excited as the details unfolded from my memory of over 12+years ago

To Potteruk :)
 

I have to say that is one very hot story and you set the scene well !! i certainly found him using Amy's worn knickers to rub his cock in very horny and you got to see him do it as well :D , i know if they were my wife's dirty knickers he was using i would hope he would do that to all her other dirty knickers!! I bet you had a good wank when you got the chance though ? or maybe gave Amy a good hammering ;)

Both actually!

i dont blame you on both counts !! i quite fancy using Amy's knickers myself ;)

Just remembered another. I used to see this girl and we booked a week in Spain together. Two weeks before we due to fly out we split up - I found out later she'd stared screwing one of her make housemates.
We both tried to get someone else to go with us rather than lose the money but couldn't. So we stupidly agreed we would still go "as friends". Massively frustrating holiday for both of us. She got really drunk one night and was sick everywhere and I had to clean her up, after getting reception to let me into our shared hotel room that she'd locked me out of.

Anyway I had to watch her in a bikini all day and so I had a wank in my single bed next to hers every night when I thought she'd gone to sleep.

One night she again had a bit too much to drink and got a bit tearful. Probably feeling guilty about being unfaithful. For some reason I got up and got in her bed and gave her a hug. I just had boxers on but a raging hard cock underneath. I found she had just a pair of pants and a vest top. We fell asleep.

When I woke up, and I blame this on being so horny, I assume in my sleep I had pulled up her top so her breasts were covered only by the thin sheet we were under. I didn't know what to do, scared if I moved a woke her she'd pulled her top down.

I managed to get out the bed without waking her and proceeded to stand by the bed, drop my boxers and started to wank. I was shaking as I knew her tits were just under a thin sheet. After a couple of minutes I decided to risk it and I moved round and very carefully slid the sheet down until there they were both on show. I wanted off there facing her in the early hours of the morning and she didn't wake.

I crawled back into my own bed and fell asleep. When she woke in the morning g the tits were again hidden from view.

We had a couple of goodbye fucks 6 months or so later.