A scary and exhilirating experience.
During my senior year at the university, I lived in an apartment-style dormitory, with men and women living on alternating floors in the 15-story building.
Living in that building kept me in a near-constant state of sexual arousal, with hundreds of beautiful or merely cute young girls studying, doing laundry, and talking with friends, oblivious to the impact their natural beauty was having on us guys.
Several times I was lucky to find freshly-washed and dried ladies' panties still warm in the laundry room, and in a previous post I wrote about how incredible it was to steal a pair, run up to my room, lock the door, strip naked, lube up my cock, and stroke myself with the fresh panties until erupting a huge cum-load into the soft warm pink or white cotton fabric.
In one of my classes we were assigned a group project, and I discovered that the hottest girl in my group also lived in my dorm. We had to work on the project on a Saturday, and Amy (not her real name) gave me the key to her dorm room on one of the women's floors, because she had to work off-campus.
I went down to her floor, the door key in my hot little hand, and knocked several times. No answer.
I waited another 30 seconds, knocked again, then unlocked the door and went inside.
There was no one inside the apartment. I found the project folder lying on the kitchen table and was about to grab it and leave when I had a dirty little thought about investigating her bedroom.
I stood by the kitchen table for some more moments, indecisive, and developing a huge erection in my shorts.
Finally I decided to act. I went to the bedroom I figured was Amy's and walked in. Her bed was unmade, so I stripped naked and got into her bed. I began dry-stroking myself and one liquid bead of pre-cum welled up at the tip of my cock. I rolled over on my belly and wiped the fluid into the bed sheet, then got up and inspected the bed. Several of my body hairs had fallen on the sheet, so I swept them off the bed onto the carpet.
I then carefully opened the top drawer of her clothes chest, examined her panties, and picked out some pretty white ones with a little left-over crotch stain.
Remember, I am totally naked with a boner, standing in the bedroom of this girl who trusted me enough to give me her room key, and who would be shocked if she had walked in on me.
I spotted some Vaseline on her nightstand and decided to risk it. I knew one of her female roommates could come in at any moment, but my heart was pounding so fast in my chest that I knew there was no turning back.
Still naked, with my boner bobbing in the breeze, ears alert to the slightest sound from the hallway outside the dorm room, I grabbed the Vaseline, smeared a finger's worth on the head of my cock, wrapped the panties around the head, then began stroking it up and down, up and down.
The building pleasure was so powerful, so intense, that within a minute of starting, my body was convulsing in pleasure as shot after shot of warm waxy cum came out of the tingly tip of my cock and filled the crotch of the white panties.
If Amy or anyone else had walked in on me at that moment, I could not have been able to stop myself or hide what I was doing.
After I caught my breath, I quickly but carefully wadded up the panties into a ball, so as not to spill any sperm on her bedroom carpet, got dressed in 10 seconds, gave the bedroom a lookover to catch any evidence I might have left, then grabbed the project and got out without being caught!
That memory is still so powerful that I replay it sometimes while I am jacking off, all these years later. It never fails to get my heart racing and the sperm flying out of my cock and splashing onto my belly!