Who Who?

So VacantNJ, Gravemind and I were doing our weekly Overbrook trip to survey the demolition, when Kevin noticed this guy perched on top of a ward door. As we approached, we spooked him and he flew right by us down to the end of the ward. We turned around to see where he went and he was trapped in a small room. I managed to get a window open and luckily he figured out to get the hell out.