Neta me lo juras comes from everyday Mexican Spanish slang, where neta means truth or really and me lo juras means do you swear it. The phrase has long been used in conversation to challenge surprising claims, and short voice clips of it spread online as a reusable reaction for memes, chats and video edits. Its popularity comes from how universal the moment is, since anyone can use the same incredulous line when a story sounds exaggerated, suspicious or simply too good to be true.