Scared. A well-built young guy came on to me in the shower at the gym a couple years ago. It was hard and no bigger than my thumb. Not wanting to hurt his feelings, I said, "no thanks, I'm str8", and just got out of there in a hurry. I guess it was more my fear of not wanting to appear to be a jerk, than being afraid of his dick. He turned out to be a cool guy and on occasion we would spot for each other.