will the birthday boy and his friends have all been drinking a lot of water and are busting for a piss and good at holding and holding a lot?? it could be a tradation where the birthday boy has to have sex with his bladder really full. maybe he and his friend's are not allowed to pee until the end? 

did you swim with your bladder full??? drink a lot before pissing? have you held your dick to build up pressure other times? I like that feeling and have done it a lot of times. even done it without peeing afterwards. 

did you swim with your bladder really full? how much did you drink before a swim meet? ever showed off how big your bladder got? did the others hydrate well too?? did any horsing around while bladder was full? have you held it other times seeing how full it could get?? I would hold it in class and go to next class still holding.

Did you do any diving with your bladder really full??? how did you like your college classes and friends you made? Did you see how many beers you can drink without pissing? when clubbing i will see how many i can drinking then when its really hard to hold I go on the dance floor and dance. feels really good dancing with my bladder full and i will keep on dancing to hold it in. Did you do much weightlifting for diving???? did you get your bladder really full other times???? 

Hi do you personally make any peeing videos and are there any on this site?