Lyra ran into the Great Hall where a few people were still eating their dinner. She looked up to the teachers' table; the only teacher sitting there was the new charms teacher, Bellatrix Black. "Professor Black!! Professor Black!," she screamed. "The dementor is in the Gryffindor Common Room! Ron Weasley is trying to hold it at bay, but I don't think he's doing a good job! You'll have to come and help us!"
Lyra led the new professor she had just gotten to know up to the Portrait of the fat lady. Then it occured to her that this wasn't a member of the Gryffindor house...was she allowed to tell her the password? But a slit second after that thought had crossed her mind she remembered that this was a professor, surely they were allowed to do this sort of thing....but just in case, she would somehow try to get the dementor out of the common room, into the corridor in front of it.