As long as men and women have existed, men have desired women younger than themselves. All of biology and society is tilted in this direction, whether it's the fact that men remain sexually potent far longer than women do or the squishy idea that men become "distinguished" as years go by while older women look, well, "old."

Hey, we didn't write the rules, we're just teling you how it is.

In June 2011, Hugh Hefner's then-fiancĂ© Crystal Harris, 60 years younger than the aged playboy, skipped out on the wedding and said some not-very-nice things about her (apparently) heartbroken old beau. A year later, the two reunited, and on Saturday, the news broke that they again planned to wed, this time in a small ceremony to be held on New Year's Eve at the Playboy Mansion. 

Let's face it: Hugh Hefner is a freak, in the most enviable way possible. His entire romantic life since founding Playboy has been a series of young sexpots. These days his girlfriends, Crystal included, are not young enough to be his daughter; they'd be on the young side even for a granddaughter.

We may never see someone quite like Hugh Hefner again, but that doesn't mean cradle-robbing isn't a popular practice for men. And seeking mates with that father-figure quality (evolution makes them want reliable providers, y'know) continues to occur in the female of the species. Here are 15 hot young things who've been snatched up by wily old coots.

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