This time, the surprise actually shows on Dirk's face, because of all the answers he was expecting, it certainly wasn't this one. "Professor Donoghue?" He's had classes with him before, surely Bro didn't miss their conversation about Dirk getting caught up in classes over the journals. Or maybe he was focused on this meeting, which isn't too surprising, considering how it started out.

Still, he can see the smile, and it probably means that if Bro weren't a Strider he would be beaming with the dumbest grin right now. It's hard to disapprove of someone when Bro talks about them like that. "How long has it been going on?"