Hugh Hefner is in the house, or so we think. We can't say for sure because his son Marston doesn't see his dad every day, and we're not technically in the house, anyway. We're in the game room, a low stone outbuilding separated from the Mansion by about a hundred meticulously landscaped, hedgerow-lined yards. Like the rest of the Mansion, the game room has a decided swinger-in-amber vibe. There's a pool table, a Foosball table, a jukebox, some Reagan-era arcade games, and a little seating area designed to look like the interior of a '70s conversion van. On this particular afternoon, there is also Julie McCullough, a blond Playmate (February '86) perched on a high stool, smoking a cigarette, playing Centipede. And Marston and me, shooting a game of eight ball, talking about what it's like to be the son of Hugh Hefner.

Marston doesn't actually live in the Mansion—not anymore, not since his parents split up in 1998 and his mom, the blond Playmate Kimberley Conrad (January '88), moved into a more modest house that adjoins the property. He's 18 now, about to graduate from high school, a tall and lanky kid with heavy brows, watchful, slightly sad eyes, and a complexion that says "I spend too much time playing video games." He has none of his dad's swagger or mothlike attraction to the bright lights of Hollywood—which you could attribute to a young man struggling to define himself in opposition to his famous father, or to the fact that they just don't spend that much quality time together these days. Marston doesn't make it over every day. He's usually here on Thursdays, though, for… backgammon night.

"It's a regular thing," he says. "We talk about what's going on in school. My latest stuff. I've always been able to go over and talk, but when it came to doing something together, we'd have to plan it out beforehand. He's a really busy guy."

Do you keep a bedroom here?

"No," he says. "I did."

For a kid who spent the first eight years of his life in the Playboy Mansion, the mythical home of American male sexuality, Marston seems to keep this place at arm's length, as though he is from this world but not of it. He seems to have no interest in, say, scoping chicks with Bill Maher at the Midsummer Night's Dream party. He does not wear silk. He is a former leader of the Human Rights Student Task Force and has strong opinions on Darfur.

Still, he's had what has to be the world's most illustrative, intensive at-home sex education. Right?

"Well, as a 15-year-old kid, seeing naked people occasionally, that's—it's just the lifestyle of growing up as Hugh Hefner's son, in his shadow. It's not a boo-hoo sob story. But it's not the same as every other kid."

Marston leans over the table, pulls back the cue, and shoots clumsily. "You'd think I'd be better at this." A Playboy publicist, tasked with keeping an eye on things—this is Marston's first real brush with the press—is chilling in the van room, watching. "My, like, expectancy for what girl I'm going to get is, like, so fucked-up. I've just been around really hot women my entire life, so the average high school girl won't do it for me. But instead of making me really care about looks, I look for the personality and a personal connection. Because I've been around looks all my life, and it's like, if I can't talk to her…"

We couldn't agree more. But on to the more profound question: When you're Hugh Hefner's kid, do you learn about sex like other kids do, by pilfering your old man's Playboys?