Yeah, all the time. I usually wear underwear with boardshorts when I swim because it's more comfortable than normal swim trunks with the netting, but recently I've mostly just swam in a pair of briefs.
At the beach, swimming pools, hotels... even did it once at a waterpark. That was a fun experience! I always use the same pair because they look and dry a lot like speedos, so they don't really raise any suspicion. Feels kinda thrilling and naughty to be out in public because you're the only one who knows, and compared to normal swim briefs they don't leave that much to the imagination. To
