Author's note: I don't strive for realism. I like to push my characters to the limits of believability. That's fun for me. If non realistic behaviour bothers you, there are many authors who write longer and more realistic works than me.
...
Amber was 3 years older than me and had often seen me as a nuisance growing up, but in the last couple years things had changed. We both got into rock climbing around the same time and it wasn't long before I was flashing her projects.
One time I flashed a V6 she was working on and she turned bright red when her boyfriend at the time said I was better than her. They didn't last long.
But she took it in stride and even encouraged me to do competitions.
We both got better and now that I was 18 and our parents would let us, we were on our first climbing trip.
We had done Yosemite, and now we were in Patagonia. We were going for an ascent of a big wall just at the tail of the season before it became too cold. It was cold though. Cold enough to make your grip better but also cold enough to mean precautions needed to be taken.
We each had a large bag with warm stuff for the night we would spend up on the wall. An experienced climber might do it in one day but we wanted to be able to take out time.
When the day arrived we hiked up to the base and I began on lead. We made quick work but it was even colder than we expected. The wind pushed our roped bags away from the cliff and back against it with thud after thud as we climbed.
When we found the spot for the first night Amber began to pull the bags up. That's when something went wrong. When she disconnected my bag and put it on the portilage, there was a sound of friction and then she gasped. Her bag was plummeting 700 feet down the cliff wall.
She watched with her mouth agape as her bag hit the wall and bounced away, making no discernable sound against the wind as it disappeared into the trees at the base of the cliff.
"What the fuck was that?" She yelled, looking at me.
I had, in hindsight, stupidly connected the bags to each other through a loop. When one was released the other had no counterweight to stop it pulling through the loop and dropping.
"Fuck." Was all I could say in response.
"Ya fuck is right." She said, her voice almost as cold as the wind which was picking up.
"You better have a big sleeping bag little bro." She said, tossing my bag to me.
After closing the cover to the portilage we unrolled the sleeping bag and got in. The wind buffeted the walls of the tent-like structure dangerously but I knew I had connected it right, Amber had double checked my knots with justified distrust.
We were down to our long underwear in the sleeping bag which was barely big enough for us both. We didn't complain though as it was warmer that way.
Amber shoved her hands down the sides of my pants and I winced at the cold fingers.
"And don't you dare do the same." She said seriously.
She turned her hands both ways to warm them against my skin.
Even though they were freezing, I didn't complain as she rubbed the sides of my butt with her hands.
"That's better." She sighed after a few minutes. "We should get some sleep."
She turned around, scooting back and pulling my arms around her for warmth.
I could see her neck in the dim light from the moon. It was long and moved as she breathed. I found myself pulling her closer, unsure if I was doing it for warmth or because it was the closest I had ever held someone before.
I placed my face against her neck and she gave an approving "mmm."
We stayed like that for a few seconds before my body betrayed me.
"What the fuck Tom?" She yelled, shifting away from me as far as she could, which wasn't very far.
"Sorry!" I said. I could feel my face warming with embarrassment.
There was a long pause.
"It's fine. I'm sorry." Amber said quietly. "I know it's not something you can control."
I calmed slightly at her words but my heart was still beating out of my chest at the reality of being caught with an erection pressed against my older sister's ass.
"Thanks."
"So..." she said awkwardly. "Is it gonna go away?"
"Uh, I don't know."
"Right." She said, turning her head to look at me.
"Well, we need to get some sleep and honestly I'm getting cold just having this distance between us."
She looked at me with an unreadable expression.
"Right." I responded, not sure what else to say.
"Ok so, maybe just trying to think about something else ok?" She said, shifting her back and butt against me and pulling my arms around her again.
Her butt pushed firmly against my still hard member, but she was clearly determined to ignore it so she could be warm and sleep.
I held her like that for 15 minutes, trying desperately to think of anything except my sister's ass against my cock. Nothing worked.
"Hey, why don't you just deal with your situation and then we can both get some sleep comfortably?" She said out of the blue. I had thought she was sleeping but I suppose my hard dick was distracting her as much as it was me.
"What like..." I mumbled.
"Yes, rub one out real quick and we can sleep." She said, slightly frustrated.
"But what about you?" I asked dumbly.
"Well I'm not going anywhere obviously."
"Right..."
"Come on get it over with, I'm serious." She hissed.
Hesitantly I pushed down my long underwear and briefs, freeing my cock which was now resting against my sister's long underwear covered ass. I turned slightly so my cock was aiming up instead of pushing against Amber, and I began to stroke it.
The next few minutes were a mix of intense and awkward as my breathing got more laboured and the portilage shook slightly from my masturbation.
Amber, for her part, tried to appear like she didn't know what was happening, although I thought I noticed her breathing increase a bit too.
