I once heard an older gentleman explain his attraction to young women....."It's easy," he said.  "As long as the money is flowing, I know she'll be around.  When I get tired of her, I just cut off the money and she's gone."  Keeps it simple.  Well, I don't think every older man who has a relationship with a significantly younger woman feels that way, but it certainly did give me a moment's pause!  I've also known older women who had a relationship with a younger man but somehow, that wasn't quite as accepted socially.  When us older women remark about the September/May situation, it can range from catty snickers to quiet resignation that one less male is in the marketplace.  However, I've also seen situations with a time-forward sequence where the older man's physical or mental health deteriorates significantly and the younger woman is trapped by wanting to hold onto the money or she bears the brunt of closing down her world by taking on the physical care for the man at a time when she could be more fully expressing her maturity.  (And yes, surprise ladies, there are men who seek a younger woman so they will be cared for in their later years).  So yes, there can be love at first sight, and maybe the 20-something really is into wrinkles and false teeth.