"Er." Al said. "Um." Clearly Alex expected something else of him to the point of attempting to poke it out of Al, but what was it?
Alex looked constipated and excited at the same time. It was puzzling.
Al focused and wondered what would he be feeling in a similar situation. Similar to the point. He wasn't about to imagine himself interacting with 'Professor Black'.
Perhaps... maybe... no.
Finally he thought he had it identified, so he reached out his hand and delivered three pats on Alex's shoulder.