Love cock slips and I love discussing them!!
I'm been on both sides of this; my dick has slipped out and I've seen guys who's dick has slipped.
I guess it CAN be embarassing but I really don't think its a big deal between friends or in a dorm situation. We all have dicks and stuff happens sometimes!
I've had my dick slip out of my PJ's when I was a kid and once I hit puberty stopped wearing them because of that. I have had my cock slip out of some short gym shorts in front of my friend's when I was freeballing in them.
As far as seeing other guys 'slips', PJ's and boxers are both pretty prone to them because of the open fly gap.
In the college dorm, a Phillipino looking guy asked if he could come down to my room and study with me one night. I said sure (although he'd never asked that before). Well, about 8 pm or so he came walking down the hall to my room with his books. He was wearing his PJ's. Pretty much no one else on the hall wore PJ's; most of us wore briefs and never really stipped down to them until it was time for bed.
Anyway, he came into my room and sat down on the edge of my bed and I could easily see his nice black pubes through the gap. He knew it and kind of laughed...we just went ahead with the study session although I was frankly "Turned On" seeing him like that.
Another time I was staying at a hotel at the beach with a couple of friends. One of the guys was hot, sexy and 15 years younger than me. He got in bed late after everyone else was already asleep. Next morning we got up and an hour or so later our friend did. He must have just crashed into bed; he forgot to take his eye glasses off! Anyway, he pushed the covers back and his dick had slipped out of his boxers!
Nice uncut black dick too! He put it in his shorts and got up and everyone acted like it was nothing.