Quentin thought that Snape could be rather more amiable and amusing if he took hold of that broomstick that was wedged far up his arse and removed it. However that didn't seem likely to happen anytime in the near future and so he figured he would just deal with the man. But not without his usual joking and humour and even flirtation if the mood struck him. Some things just weren't going to change.
He did honestly wish to see his grat-grandfather's portrait though. The elder Quentin Trimble had died the year before his birth - devoured by a Lethifold, much unfortunately, while enjoying a retirement vacation with Quentin's grandmother. He had seen many photgraphs, heard many stories, but speaking with the portrait would be altogether different.
He arrived at the Headmaster's office at eight, sharp, and murmured the password Snape had given him before passing through the doors and stepping inside. His gaze soon enough landed on Snape, himself, and he nodded his head.