When you are high, drunk,or both and want to do something fun and some one you are with starts complaining about everything.
Person 1: Man we should egg that house
Person 2: No man we could get caught, I wanna go home
Person 1: Will you stop being a fucking buzzkill
When your having a good time then somebody uninvited shows up and kills the good time you were having. Being high and drunk is optional.
James is such a vibe killer no one ever has fun around him