Meizon ...

The only reason I don't really like meizon is because it reminds me of 'maison' which is french for house. I looked up that 'medi' means middle in latin and age is aetatis and love is 'amor'. I'm not sure what you could make of that though. Mediamor. Doesn't really sound like a good name... I think it will probably be hard to find a good fit.

I'm not one to give out labels but there already are labels for young women that like older guys, like gold-diggers, grave-robers (which I find hilarious but probably shouldn't...), cheetas I think I heard once although I'm not sure why... So although people might not like labels, they're already out there so why not get a nicer term? Instead of being called a gold-digger, or being called someone with 'daddy-issues' they can actually put a more formal term to it. Not to mention the term can be used for girls and guys that like people older then them, whereas most the ones right now are slanted towards girls.