"You've got to pull over," I screamed.
"I'm not stopping again," my older brother said, "it's not my fault you had that extra coffee, I warned you."
"You're such a fucking dick," I mumbled.
I was desperate now, my bladder felt so full and I had a burning sensation in my crotch. My step brother could be such an ass sometimes.
He had come to get me from university to give me a lift home for the Christmas holidays, which was very sweet of him, but now he was being a twat. I really needed a piss and he wasn't stopping.
"I'm going to piss myself in a minute," I warned, "all over you fancy leather seats." I was shifting my ass around on the seat, fidgeting seemed to help but I knew I was actually going to piss myself soon. I moved my hands between my legs, pressing in hard on my pussy.
My step brother, Ben, stared down at my lap, my hands pressed against the crotch of my skinny tight jeans. "Watch the road," I shouted, "find somewhere to pull over."
"I'm not stopping Beth," he said, eyes returning to the road, "if you piss on my seat you're going to pay."
"I can't help it," I said, "you have to stop."
"Nope," he replied finally, his eyes flicking back to between my legs and then back to the road.
I brushed my long blond hair behind my ear. Shit, what was I going to do, 18 years old and about to piss myself, I was desperate. I had warned him though and he didn't listen, maybe I should just piss myself, I thought, that would teach him a lesson.
Right then the thought of pissing myself strangely really turned me on, of relieving myself into my jeans. I had thought about it before but shook it off as perverted. The thought of my step brother seeing me do it added to the perversion, and turned me on more.
The more I thought about it the more I needed to pee, I was pushing down so hard now on my crotch, trying to stop it. It was no use, I could feel it coming, I was desperate for the release. My urethra was burning.
Oh god, I was going to pee myself definitely, part of me so ashamed the other part desperate for the release, partly turned on by the thought of wetting my jeans and filling the crotch, watching it spread.
The thought was too much and it started, I moved my hands as a small wet patch started to appear on my crotch, it felt so good to let go.
"I'm peeing," I shouted, "I can't stop it."
Ben looked over and his mouth dropped in horror as he looked at my open legs, the wet patch spreading, beads of piss pushing through my tight jeans.
God it felt so good, the warmth spreading over my crotch, starting to dribble down my ass crack, tickling my anus.
Ben spun the wheel hard left on to the hard shoulder making me squeal.
"Get out," he shouted, "you're ruining my car."
I pushed the door open and stood up outside, the car shielding the view from other cars, piss still pouring out of my pussy lips, the wet patch spreading down the back of legs, I could feel the pee running down the inside of my thighs and over my calfs.
It was such an amazing feeling, my full desperate bladder, the pain subsiding, all that piss dying to come out released into my jeans. It was making my cunt wet with not just my piss.
Ben watched my tight ass and long skinny legs as piss stained my jeans from my crotch downwards, he watched in fascination as it ran out the bottom of my jeans, over my ankles and trainers, and then started pooling on the floor.
I finally stopped, my jeans drenched in piss, a small pool in the crotch of my panties. I could feel Ben's eyes burning into my ass, I felt so horny now, what was wrong with me.
"I can't believe you just pissed yourself," Ben said, "and in my car."
"Fuck you," I said angrily, turning around "I warned you and look what you made me do."
Ben looked a bit ashamed of himself, his eyes looking at my flat toned stomach, and my narrow hips, my jeans were low on my hips, showing off the muscles that led down to my pussy. His eyes lowered to between my legs, a giant wet patch.
I was sure that was his cock tenting his shorts, that made me a bit wetter. I know he was my step brother, but there was no denying he was fit. Short dark hair, muscular body, but slender and athletic.
He looked up, "whatever," he said, "you're not sitting next to me now, get in the back, there's a towel there you can sit on."
I couldn't be fucked to argue, I got in the back seat, sitting behind him, I didn't want him being able to see me.
"You're going to pay for making me piss myself," I said.
"Whatever," he said again, and started driving.
I sat in the back, my bottom half covered in my own pee. My panties were so wet and not just from the piss, I was turned on so much, I could feel the warmth in my cunt, the juices leaking out, my swollen lips.
I pushed a hand into my crotch, my legs closed but my hand fitting into my thigh gap. The other hand I used to squeeze one of my small breasts through my tight stone roses t-shirt. I tweaked my nipples sending jolts through my body to my pussy.
The t-shirt was short so I ran my hand over my flat stomach and to the waistband of my jeans, silently undoing the button.
I started rubbing myself with the hand between my legs, pushing down onto my cunt, applying pressure. I had to stop myself from groaning. My hand was getting wet with my pee, covering my fingers. I checked the rear view mirror to see if Ben was watching me, he wasn't, so I lifted my hand to my mouth and sucked a finger, tasting my piss. It was so bitter, but tasting it turned me on.
I pushed my right hand down the front of my jeans, running my fingers over my soaking wet panties, pushing them into my engorged pussy lips. Running two fingers up and down my slit, covering them in my juices, then up to my clit. A small groan escaped me.
"You alright back there Beth," my step brother asked, looking at my flushed face in the rear view mirror.
"Yeah," I replied, "just a bit uncomfortable in my wet jeans."