Jizzing While Trying On Swimsuit

Until the age of 13, I had worn two types of swimwear in my life. When I was really young, I wore a short-sleeved black and green wetsuit. As I got older, I progressed to shorts, with my two favourites being a light blue pair that dropped to just above my knees and an orange pair of board shorts that went just below my knees. That all changed one day during a school swimming carnival in my first year of high school. I was on my way to the food stall to buy sausage on bread (a classic Aussie snack!). To get there from the stands, I had to walk past the starting blocks of the pool. While I walked past, I noticed my friend Adam, who was in line preparing for his race. He waved to me as I walked past, and I waved back. Suddenly, I looked at the swimsuit he was wearing - a red pair of swim briefs that were fairly small and tight. As I continued to stare, I marvelled at how awesome the suit looked on his body. Adam's skin was fairly pale, so the red briefs stood out quite a bit.  I had seen many people wearing swim briefs in Australia, so it should not have been a big deal. However, I continued to stare at Adam's suit, taking in his whole body. He had short blond hair, a thin build but really strong-looking legs. My eyes wondered up to his crotch and I could see his semi-erect penis, with the tip halfway up the swimsuit. His thin blond pubic hair was barely noticeable, but stuck a centimetre or two outside of his suit. Adam noticed me looking, and I saw his penis start to twitch and rise. In embarassment of getting caught, I rushed to the food stall to buy my sausage, not daring to look back. It took a few minutes to get my sausage as there were plenty of people in line. While I was in line, I couldn't stop thinking about Adam in his red swim briefs, and felt myself getting hard. As I headed back, I saw that Adam was now at the front of the line. He glanced my way and grinned, as if to say ''it's okay that you looked''. I grinned back, this time glancing at his crotch much more casually. Now his penis was fully erect, touching the waistband of the suit! Suddenly, Adam was called to go to the blocks to start his race. I stood where I was, now getting a view of Adam's cute red butt! My little friend downstairs was now fully erect, and I rushed back to the stands to avoid anyone seeing. As the race started, my eyes were fixed on Adam as he rocketed across the pool. Me and my other friends cheered him on from the stands. He came second in his heat, and quickly got out of the pool. Now that his suit was now completely wet, it clung even more tightly to his body, and his bulge even more noticeable. I only managed to see Adam's bulge for a few seconds though, as he quickly got a towel to wrap around him. Darn it! The day continued normally, with each year group getting a chance to race if they wanted (I did not participate), then there was a really cool students vs teachers race, followed by free time where everyone got to splash in the pool for fun. During this free time, I talked to Adam at the edge of the pool about where he bought his swimsuit. He told me the name of a sport store and I decided to go there after the carnival was over. As I headed into the store, I felt a rush of excitement. My boner was semi-erect, and as I found a pair of red swim briefs to try on, it became fully erect. I got inside a change room and took off my clothes, noticing a sign that said underwear had to worn while trying on swimwear. I slipped the red swim briefs under my feet and across my legs, enjoying how exciting the moment was for me. I pulled the swim briefs over my underwear, looking at my reflection in the mirror. I felt my butt, hips and boner through the suit - but something didn't feel right. I didn't want to be wearing any underwear. Just the swimsuit! Sheepishly, I looked around the room for any cameras or staff. When I was sure the coast was clear, I pulled off the swim briefs and my underwear, and stared at my naked body in the mirror. I was still fairly short, having not yet had a growth spurt. There was barely any pubic hair on my penis, just a few short strands. My boner was about 3 1/2 inches long, uncut, pointing straight up at the ceiling. For a minute I stood there, glancing at the mirror and wondering whether Adam's naked body looked like mine and also whether his penis looked like mine. At this thought, a small amount of precum came out of the tip of my penis, dropping onto the carpeted floor of the change room. I was clearly very horny, and decided to try on the red swim briefs again - without wearing any underwear! As the briefs touched my boner, I felt amazing. This is the feeling I wanted! When the briefs were completely on my crotch, I looked at the mirror and felt my butt, hips and boner again. This time the feeling was electric. The briefs fit nice and tight on me, just as they did on Adam. As my hand brushed past my boner, I had an idea. What if I rubbed myself in the swimsuit and stopped before I jizzed? Excitedly, I knelt down, getting as close to the mirror as possible. My left hand began rubbing my butt in circles while my right hand rubbed my boner through the swim briefs. I looked in the mirror, first pretending that I was Adam and masturbating like this in a pool change room, then pretending that my right hand was Adam's hand and he was rubbing against my dick! I continued like this for a minute or two, stopping as soon as I could feel the tingly feeling in my balls, pausing, then starting again. About 3 minutes in, I was rubbing faster and harder than ever before, and as I looked in the mirror, I fantasised that both Adam and I were in that change room together and we were rubbing each other's dicks through swim briefs. The feeling was building up again, and I prepared to stop. But for some reason, I rubbed downward one more time. On this down stroke, I realised with horror that I had gone too far to stop. My breathing stopped. My body stiffened. My feet clenched. My balls tightened as young early teen cum shot out of my penis, rope after rope after rope, landing in the red swim briefs I had just tried on. Guilty, I looked at the mirror. The entire front of the swim briefs were soaked, even the strings! I quickly got a tissue out of my school backpack and cleaned up all I could. When I was finished, there was still a large black wet spot at the front, and a milky white stain on the inner lining. Realising I had been in the change room way too long, I quickly put my clothes back on and hurried out of the store, thrilled but extremely embarrased at what I had done. The red swim briefs that now contained cum remained in the change room, waiting for someone to discover...