Hmm. Perhaps he and Ottiley know each other someway somehow? They both came from crap backgrounds and dragged themselves out mostly through will and if nothing else Adam is always down for grabbing a drink and bitching talking about things.
With Thomas they possibly could know each other from years earlier since my thinking is that Adam and his mother moved to one of the rougher areas of town after being freed. So maybe it was the same neighborhood? Or, depending on Thom's tolerance for mouthiness, Adam may not be attached, but that doesn't stop him from searching out a reigner occasionally...
Tamsin might run into him either at school or the coffee shop that she works at? He's a caffeine junkie and is probably here a lot.