Main-Characteritis
When someone thinks that they're always the smartest, toughest, prettiest or just the most interesting person in the room without actually being able to back it up.
"Why does Alyssa always talk so loud? It's like she wants the people next door to hear her, too."
"Just try to ignore her, she has Main-Characteritis."
"Just try to ignore her, she has Main-Characteritis."