Coop likes Reid! He's bright for one which is a trait Coop always appreciates, but he's also shown to be able to be playful (Tetris!!) which he values just as high. He's not hard to talk to and there are a few similarities between them, at least from the looks of it, and being FBI is just one of the reasons Coop will gladly poke at him and get to know him a bit more. Also like Albert Coop can't help but see a bit of himself in Reid, which while not exactly a positive thing doesn't really harm the impression he's making. c: the tl;dr is GOOD GUY, pleased to know you, and wouldn't mind knowing you a bit more.