I feel stupid replying to a post written 5yrs ago, besides his erection has probably subsided by now. As it's been mentioned before it depends on the circumstances and the location. Totally agree that when it happens in public nudist areas he should make an attempt to cover up. Either roll on to his tummy or go for a swim. I remember an occasion a few years back here in the UK at the clothing optional club I belong to A new guy had turned up ( single men allowed ) and was being shown around and introduced to people that were scattered around the lawn area by a member. Everything was ok until he came to " Mary", a well developed mature lady, who liked to tease. Well very soon she had managed to get his blood flowing, and the end result was a massive erection. She said you better cover that up and save it for me later. Trying to cover it was a real problem. It really was large, the towel was hanging on it, rather than covering it. It was quite obvious what was beneath.