Negative Ned 

A person that no matter how positive the room is, brings in his negativism and thus drains the room of its positive vibe.

First Person: "Here comes Fred again."
Second Person: "Nah, you mean Negative Ned."

Negative Ned by Poop Stain Barney May 17, 2011

Negativeness 

The expression or state of being under which an individual shows negative emotion.

But I have every right to annoy you enough to get out of the negativeness.

Negativeness by R.Minsif75 March 1, 2023