pathnarc

Abbreviation: pathological narcissist. essentially a person who is determined to stay childish, win/lose and be a complete selfish dickhead unless the person they are interacting with has something they want (e.g. being nice to your boss but a dick to everyone else)

"I reckon Johnny's a pathnarc. He totally doesn't give a shit about other people and he's only respectful if you've got something he wants."