The phrase comes from Turkish slang, where yarra is a vulgar word used jokingly among friends rather than as a serious insult in this context. Clips repeating bak yarra spread through Turkish social media, gaming chats and WhatsApp groups as a shorthand teasing reaction. Its appeal is the rhythm and delivery rather than a known film or show scene, so it works as a portable soundboard joke that Turkish speakers instantly get and other viewers recognise from repeated meme use online.