Men seem to only truly want what they can't have. Or what they think they can't have. In my experience, many many men have fantasies about being with older women. Likewise, many of the husbands of friends and male friends I have express the desire to be with a younger women. 

Anyone care to speak to this? Is it the challenge? The risk? Or is it simply the natural human urge for novelty?

(Girl at the right was forwarded to me by a 50 yo male friend of mine, saying he would "risk 20 years of marriage to have this [young woman] ride on his cock for twenty minutes or so.."  )