Aidan will be affected and a lot less... cheerful. Or rather, a lot more vocal about how there's actually a lot of things that aren't as super-awesome as he tries to pretend that they are! Self-censorship is going out the window and a healthy dose of negativity is taking its place. If he gets the chance he'll also be a lot more physically affectionate around the people he likes - this can range from proper hugs to hands on shoulders to hair-ruffling. Open for plotting!
I'm not sure what to do about Reid yet, seeing as the guy is a walking pile of inhibitions but chances are good that he'll at least be somewhat affected. Open for ideas!