An incorrect spelling of the phrase Grammar Police, a derivative of the Grammar Nazi.
The original poster is obviously not part of the "grammerpolice" due to his misspelling of "grammar" and his lack of a space between grammer and police.
When a person commits a grammar sin. Perhaps using a form of a word that is not grammatically correct, misspelling a word or the misplacement of punctuation.
Person one: Hey, how've you been?
Person two: How've ain't a word.
Person three: Both of those statements are grammarasphemous.
Person four: Yeah you guys have comiited Grammersphemy.
Someone who does it for the gram. Cole bought a new pair of kicks so he had to climb a building and post a pic for intagram. Grammers post regularly to instagram and often use their posts to generate income.
The alleybehind my building is usually full of grammers trying to look hard.