A larper is a general insult to describe someone. This insult can be used in a variety of ways and can substitute things like: asshat, moron, fucker, etc. It can also be used as a verb or adjective.
Man, he is such a larper, he is late again! Or There he is out larping about. That larping crazy person is going to hurt someone.
retarded niggatype shit, faggots spreading around lies about themselves being something when they're in fact some random ass noname nigga from delaware type shit.
A new-age slang term used primarily to refer to a “poser,” someone claiming to be part of a community they don’t belong in, or faking legitimacy/accomplishments.
P1: I love shoe gaze.
P2: You listen to When the Sun Hits by Slowdive and nothing else, you larper.
A "Larper" is someone that pretends to be in a certain fandom and pretends to like a certain piece of media, without ever actually consuming that piece of media.