Your parents have dropped in for a surprise visit, and they want to see what the bay looks like from the water, say from one of those tour boats. Luckily, you planned ahead: You bought extra tickets for the Bulletproof Boat Party just in case someone wanted them. (The party is held four or fives times a year, mainly in the warm months, and is co-sponsored by the Bulletproof clothing shop in the Lower Haight.) Of course, your parents aren't quite ready for a Sunday night expedition with 500 freaks dressed in skintight T-shirts, floor-length fur coats, bug-eyed sunglasses, and leather pants. And they're not ready for the music pumping out of the three separate sound systems — old-school hip hop, funky breakbeats, deep house, and anything in between. They're certainly not prepared for the, er, friendliness of the passengers. Never have they met so many people who wanted to get to know them so quickly, to find out where they are from and why they are here. But mostly, your dear parents aren't prepared for the awe-inspiring view of the underside of the Golden Gate Bridge at night, or of laser-show dolphins leaping across Angel Island, or of the San Francisco skyline twinkling as if it were synced to the beat. When, as you disembark at midnight, your parents ask if you can take them to this thing called the “Endup,” you just have to smile.