Very interesting...
When Harry got to the Charms classroom, he saw Neville waiting for him.
He walked up and whispered, Don't let on I'm here.
McGonagall put a spell on me so Ron and Hermione can't see me.
Please let everyone know and not to tell them. I'll tell the teacher.
Neville nodded.
They entered the classroom, Filus saw Harry walking up to him
and he listened carefully as Harry explained.
Filus nodded, and pointed to the seat by Neville.
The whole class knew except Ron and Hermione.
They also knew not to tell the two. Just before the bell rang,
Ron and Hermione entered the room and looked around.
Filus raised an eyebrow.
They took their seats, and watched the door.
Neville looked at Harry and winked.
Harry smirked.
Filus started the class, but everyone could see Ron and Hermione were not paying attention.
They kept looking at the door.
In the middle of class, Filus looked at them.
"Are you two paying attention to class or is the door more interesting?
Detention tomorrrow night with Filch."
Ron looked miserable, and Hermione was gaping at the charms proffessor.
He looked at them, "Anything to say or may we continue class?"
Ron shook his head, and Hermione opened her mouth,
"But proffessor I have so much studying to do. I can't be at detention tomorrow night!"
"You should have paid attention in class, Miss Granger."