The classroom has a teacher named Martha with her crazy yellow hair and polka-dotted outfit writing her assignment for the class before Angel walks in and as the door shuts....the students turn to him with their necks cracking which makes him flinch. 

"G-god....look....I-I'm sorry I'm late Mrs. Martha....I was sent to the principal's office....can you get your students to stop staring at me?"

He sees the students banging at their desks until it cuts to him being a puppet on strings as Martha controls him. 

https://youtu.be/yU5v-Jl9FtU

Then, Angel gets thrown to the other students as he crashes to the floor and he looks....broken as the students all said together;

"Ew! Gross!"

And they walked off leaving Angel on the floor looking like he was about to cry.