Rincewind

 Bedraggled and rumpled, Rincewind walks through the backdoor and immediately squeaks in shock as a waitrat passes by him. He dodges out of the way only to find himself in the path of another one and so dodges yet again. He's used to rats, as anyone who grew up in Ankh-morpork, but even those illustrious rats never get this size. He spins and runs, making it a few tables before yet another is before him and he alters his flight again. Eventually he falls behind Bar and lays panting.

Once his breathing slows, he peaks out at the bar area (having removed his hat of course) and finds a note waiting on the Bar for him. He puts his hat back on and reads.

"What?" he says obviously confused. "But I don't know…" Another note. "I can't…" Yet another note.

As they talk, the specials board is writing itself to read:"Okay," he finally says very hesitantly, "but what's a 'Happy Hour'?" No more notes appear and Rincewind gets a terrible feeling in his gut as the grain of the Bar is starting to look familiar…like he's seen it somewhere before.

He is accompanied by The Luggage; a large trunk constructed of sapient pearwood which has hundreds of little legs and feet with which it uses to travel about. The Luggage seems to have a vast extra-dimensional space within it and a habit of swallowing threats to itself or its owner. Unless I mention The Luggage it is not present, though do to its nature, it may show up at anytime.

More about the Luggage here.