Flumtastic is a word first used by Keiichi Tsuchiya, better known as the Drift King (Not to be confused by K-Brown the illegal street racing Drift King) and his friends from the Canadian underground rap group, F.L.U.M. Flowing Like Ultimate Mcs. The word varies in meaning but the general concensus is that it refers to someone or something that expels greatness and excellence while making those around the subject fall flat like pathetic underachievers that should be out on the streets begging for money to buy more alcohol to drown out the sorrows of their worthless existence like a bum (aka Bumtastic). Fans of F.L.U.M. have added on to the definition by mentioning that if you're "Flumtastic" then you are almost as good as the members of F.L.U.M.
Example 1: Damn, girl! You lookin' flumtastic right now! Don't blame me if you end up in a bed covered with rose petals.
Example 2: Drop a couple of flumtastic bars, dawg! Why don't you spit a hot 16 for the hood, homie?
Example 3 (From the freestyle MC Without A Conscience by OG Paperboy): My squad keepin' it flumtastic/ None of that "put you on blast" shit/ Just prepare to get your ass kicked and thats it/
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"