The phrase is Brazilian Portuguese slang, with karaí used as an intensifier similar to saying someone is annoying as hell. Shared mainly as a WhatsApp audio, the clip is tagged ByRM and has circulated as a ready-made reaction rather than a scene from a film or show. Its popularity comes from everyday use, similar in spirit to tu é um beta, where a short insult becomes a reusable joke between friends. People forward it in chats, drop it into edits, and use it when a complaint needs comic exaggeration.