The search of the castle continued until around three in the morning. Naturally, they found nothing. It was as though Black had never entered Hogwarts Castle at all.
Professor Dumbledore had probably anticipated this outcome long ago, but he still had to have the professors search the entire castle to reassure the staff and students, and to give the Dementors stationed outside the school an explanation.
The professors and Prefects searching the castle had it rough. None of them got any sleep all night, and staying awake was especially difficult when they were full and drowsy.
By the time Albert and Shanna returned to the Great Hall, everyone else was already asleep. Only the energetic Percy and the sleepy Prefects remained on watch.
Sure enough, walking around outside was better than staying behind to keep watch. At least they could talk to the people beside them and find excuses to slack off.
Only after dawn were the Prefects and Student Council President on watch allowed to return to sleep. The ghosts would take over from them.
As for morning classes, they were naturally canceled.
Sir Cadogan, who had temporarily taken over the Fat Lady's job, was a rude fellow. Upon seeing Albert, he insulted and provoked him, intending to challenge Albert to a duel.
"If you can come out of that painting, I'll duel you."
Albert covered a yawn with his hand, unwilling to listen to any more nonsense. "The password is 'Mongrel Dog.' Open the door."
Sir Cadogan reluctantly let them into the Common Room.
The four of them returned to their dormitories to rest. As for the password to enter the Common Room, Nearly Headless Nick would naturally be responsible for passing it on to the other Gryffindor students.
When Albert woke again, it was already noon.
Tom