The correct answer is the ones who have not already done a sex tape. We kid. The website XCritic.com, along side adult video titan Vivid Entertainment, have surveyed pervs on their pop-star sex-tape dreams and have come up with some real winners:
Katy Perry and Justin Timberlake took female and male top honors in this 12th annual "Sex Tracker Survey" of adult movie fans.
Perry took one in four (26 percent) votes on the female side; Timberlake did a little better with 28 percent of the vote.
On the ladies' side, Selena Gomez took second place with one in five votes; Rihanna came in third with one in 10 votes; and Miley Cyrus did almost the same with 9 percent wanting to see her twerk in the nude.
For the guys, we have a surprise second-place finisher: The pillow-shaped Psy, who got 13 percent of the vote. Adam Levine got about 1 in 10 notes; Usher and Enrique Iglesias got slightly more than eight percent.
Justin Bieber, you ask? Yeah, he might have abs, but he still looks like a boy. He got about 6.5 percent of the vote.
The folks behind the survey don't tell us how it was conducted, and we're going to guess it was simply an online, opt-in poll, which means it's fairly unscientific. (In other words, if you did a random poll of 1,000 pop music or adult video fans, instead of letting the most vocal people weigh in because they really want to, the results might be different).
Still, it's interesting stuff. You can find more results here (NSFW link).