Keith was a very observant child. This would've been a great strength for him - the ability to see miniscule changes in expression and body language was a talent many could never master no matter how hard they tried. Indeed, his observational skills were nothing short of incredible.
The problem was, however, that Keith didn't know what they meant. And he didn't particularly give a shit.
Sure, he could see when someone's mouth twitched. So what? And he always noticed when someone's hand clenched, or their shoulders shuddered. Who cared? What did any of it mean? Why does South America look like it would fit perfectly next to Africa? Mysteries all of them, mysteries Keith couldn't be bothered to solve. And so much of his talent was wasted on noting that the sky was blue, and the bacon was done, and yes, randomly lady in the mall, that dress does make you look fat (something Keith would inform people of whether they asked him or not)
However, rarely....very rarely, Keith had the good fortune to not only spot something most people wouldn't but he would also have a flash of insight dealing with what it meant. Such was the case for Faylen.
Keith saw the Slytherin's eyes scan the room, and the corners of his mouth move into a miniature frown. Putting the pieces together, Keith came to the conclusion that Faylen was depressed.
He couldn't think of anything he had done to make Faylen depressed, so obviously somebody else (or perhaps life itself) was to blame. However, Keith was still at a loss about what to do with this nifty bit of information, and so said the first thing that popped into his head.
"Why the long face?"