I have a kind of embarrassing story, with me being the one showing the unexpected nudity. Back in college, I went to study in Europe for a month one summer. The rooms were all double rooms, so I had a roommate. He was kind of a quirky guy, but nice enough. It was the summer, hot, no AC in the rooms we stayed in. So we were sleeping in just our underwear. Well, one night, I must have been sleeping a little restlessly. In the middle of the night, I woke up, sheets all off the edge of the bed, my tighty whities all twisted halfway down my legs. Even worse? I'm lying on my back with a raging hard on, pointing right up, the moonlight shining like a spotlight on it. The roommate was stirring a little, but I never knew if he saw me or not. We shared a bathroom with two showers, so it's not like we didn't see each other naked. But, I certainly wouldn't have expected him to see me throbbingly erect like that! :-/