Slightly offtopic, but I'm feeling a little ranty.
This whole idea that two adults cannot engage in a romantic relationship without being unnecessarily harassed, based solely on their ages, is ridiculous. Just because it makes you uncomfortable doesn't mean that the people involved are uncomfortable, being taken advantage of, or naive. It just means they have found apparent happiness in another human being. It's no one else's business and judging others based on the age of their partner (assuming both are consenting adults) should be stopped.
I'm not sure which country has it, but I'll generalize some criteria:
* Able to make rational decisions for one's self.
* Successful co-operation with already existing 'adults'.
* Able to produce surplus survival resources to enable successful raising of offspring.
By the above requirements I would suspect that if you removed an automatic assumption of truth based on chronological age, that a majority of American 'adults' would fail at lease one item on the above list. In some cases it really isn't their fault, but a fault of society failing to correct it's own conditions.
This whole idea that two adults cannot engage in a romantic relationship without being unnecessarily harassed, based solely on their ages, is ridiculous. Just because it makes you uncomfortable doesn't mean that the people involved are uncomfortable, being taken advantage of, or naive. It just means they have found apparent happiness in another human being. It's no one else's business and judging others based on the age of their partner (assuming both are consenting adults) should be stopped.