Heidi Pratt
Someone with no talent but who is so totally full of themselves they don't know that everyone's laughing at them, not with them. Pronoid.
She sounded like a cat in a blender at karaoke last night, and then spent the rest of the night talking about how much everyone seemed to like it and how all the guys were hitting on her afterward; they were being sarcastic. She's a real Heidi Pratt.