I'm a 24 y/o young male, and one of my favorite fantasies is being made the bitch of a group of young (teenage), cute guys...maybe some sort of gangbang or something... Being made to suck their cock and getting fucked roughly by them one after the other...maybe even in public. (I honestly don't know I'd want this to happen in real life...afterall, it is a rape fantasy, etc...but it is hot to think about sometimes. I probably would play out the scenario with a group of guys (safe sex and all precautions) if the chance came up though.).
More realistic, I like being dominated by a younger, hot, twinky type guy. I like a certain gentleness to him, but a firmness and roughness and even demandingness as well. I find loving domination seems to be somewhat rare, but it's really what I'm into...someone caring but who still knows he's clearly boss. MMmm...
Along the same lines, I'm an only child, but one of my recurring (weirder) fantasies is, as a teenager, having a younger brother who acts more like the older brother and took care of me (and was intimate and very dominant with me as well). Yum... Sometimes during sex with someone who's younger and dominant, it sorta feels like this in a way, which is a very comforting feeling to me.
Things like spanking and tickling I find very initmate as well...