The sound comes from a Brazilian parody titled Égua, credited to Tirullipa and linked in its file title to Rihanna's Work featuring Drake, which it playfully reworks. Égua itself is a popular Northeastern Brazilian slang interjection for surprise, which helped the parody travel as a short, shareable clip in meme edits and reaction videos. Because the single word is instantly understood by Brazilian audiences and needs no context, creators keep reusing it to flag shock or disbelief in just a few seconds.