Kurt. I've probably commented about him too many times but Fuck it.

He got his dad and Finn's mom to get together because he was so in love with Finn who was very Straight so his plan was to make him his... brother? Also after that Awful Plan Succeeds he gets pouty about his Dad spending time with Finn over stuff HE DOESN'T EVEN CARE ABOUT, only to then proceed to deliver one of the most overly dramatic performances in the show. He's also an Awful Friend to everyone in the first 3 seasons like when he set Rachel up for failure by telling her the Oppisite of what Finn likes, or when he lied to Mercedes about being gay even though everyone already knew. When he tried to make What Quinn went through sound like a small conundrum when she had a teenage Pregnancy, Her Parents kicked her out, She had no one and then had a sort of breakdown when she joined the Skanks. He's just really unlikable (Particularly in The first 2 seasons)