G'st of C's
G'st of C's is a title for someone who is the worst at everything but still thinks they're the best.
My friend is the G'st of C's. He lost the game and then blamed the ref.
My mum is the G'st of C's. She yells at me for no reason.
My boss is the G'st of C's. He doesn't know what he's doing but still gives me bad reviews.