i was at a party once with a friend of mine who was rumored to be packing down there. i'd never seen it, though. he and i were hanging out when this girl came up to him and said, "i hear you're really big".
he tried to laugh it off, but she pushed him, challenging him to "prove it". he said, "okay, i'm going to ask you this three times, just so you can back out if you want. do you really want to see it?"
she said "yes" and twice again when he repeated his question. he stood up, unzipped and lowered his pants. it was huge - i'd guess at least 5 inches, thick and hanging down his thigh a bit. certainly bigger soft than i've ever been when hard.
her reaction made me instantly erect. she stammered out "um wow. yeah. that's really um... big. wow." later on, i saw them sneaking off into a back room together.
i often fantasize about them fucking and what the look on her face must have been like when he penetrated her with that thing.