Someone who participates in the act of gooning (oftentimes addicted to it) and is proud of this.
Person 1: I beat my meat all day to those pics
Person 2: Wth is wrong with you, gooner
Not to be confused with gooner.
Coomers are people who participate in the act of cooming but are ashamed and hide it.
Person 1: I found some questionable images on your laptop; are you a coomer by any chance?
Person 2: Uhh