"Cool," he breathed through the word, trying to feign the act of dorky professor that may have interest in the student to a higher grade. He blunders almost, not sure what to do so he says 'here' and scurries to the door where he unlocks it and holds it open for Sherrinford.
He is sure to utter a see you tomorrow as the other walks, keeping his head down and working up a red face for his façade.