On Saturday night, Hermione and Harry left the bustling Gryffindor Tower and went to an abandoned classroom beside the History of Magic classroom. When they arrived, the room was empty, its contents blurred by darkness.
"Is this the place?" Hermione asked softly. She cast Lumos, and bright light cut through the darkness, illuminating the whole room. "Where's Jerry? Why isn't he here?"
Harry looked around and nodded once he was sure. "Yes, this is the empty classroom Professor Lupin told me about. Let's wait a little longer. Jerry might be here soon."
About five minutes later, Jerry appeared in the doorway, out of breath. "Sorry I'm late, everyone. Something came up on the way."
Jerry had gone to ask Professor Lupin to lend him a Boggart, but Professor Lupin had flatly refused. He didn't want a repeat of what had happened in Defence Against the Dark Arts.
At this rate, Harry and Hermione would end up in the Hospital Wing before they learned the Patronus Charm!
"Ahem!" Jerry stepped up to the front of the classroom and stood behind the lectern. He cleared his throat, his expression turning serious. "Allow me to introduce myself. I'm Jerry Green, and from now on, I'll be your Charms teacher..."
"Hold on, Jerry." Hermione gave his performance an exasperated look and interrupted him. "What are you doing? Do you think we don't know who you are?"
"Exactly, Jerry. Hurry up and teach us the spell to deal with Dementors!" Harry chimed in.
Jerry walked over to Hermione and tugged at her sleeve. "Didn't we agree on this this afternoon?" he whispered. "You're supposed to call me Professor Green. When I'm working, use my title!"
"Yes, yes, Professor Green!" Hermione rolled her eyes. "Happy now?"
Harry: ...
"All right, all right!" Jerry waved a hand.