Rrrright. He nods in return, and points the way back to the linguistics commons. And then... heads downstairs and out the door. He'll worry about long-term plans for her later. For now, home and sleep.

...And calling in sick for tomorrow. First time he'll have to make use of a substitute teacher for his own class. He grimaces- he didn't prepare anything, and he knows from experience how annoying that'll be for his stand-in.