When I was at uni, one of my housemates was on the waterpolo team. Their uniform was like speedos made of polyurethane (looks a bit like glossy latex). When I was home alone I would borrow them from his drawer and put them on in front of my mirror. They looked and felt amazing. I masturbated in them all the time, either in front of the mirror, or by lying face down on his bed and humping into them. The material made them very easy to clean! As far as I know he never knew, we’re still friends.