"Of course. You must now feel familiar with the way to my office from here. Perhaps for our future appointments, you could come straight to my office." Having his clients wait in the waiting area was a way in which Hannibal would ensure that he would have control over when and how he would meet them. Hannibal wasn't one for surprises such as a client turning up early, late or unexpectedly.
But now he'd bring Sookie a little closer, bridge gaps. Build the trust between them.
Hannibal didn't like having his office within the hospital but it was situation he could use to his advantage before moving to a different building.