Someone who posts memes that have been reposted 20 times unironically. Cries about being "discriminated against" when he's clearly OreoMortality's favorite. Akin to a puppy that won't shut up.
Person 1: Hey, did you see Heated_Flammable yesterday trying to hit up those chicks?
Person 2: Yeah, they threw their beer at him and told him to go repost in his basement.
It means: Capable of producing the white-hotflames of Hades.
The mysterious document sewn into Dragon's abdomen proclaims them to be "Highly Flammable." He shall henceforth use this a proof that he is a REAL fire-breathing dragon.