Ni-nice comes from Borat, the fictional Kazakh journalist created and played by Sacha Baron Cohen, whose 2006 comedy film made his exaggerated accent and catchphrases widely recognisable. In the film, Borat frequently approves things with an enthusiastic nice, and short clips of that delivery were later lifted for soundboards, reaction videos and meme edits. The sound works because it needs no context: one familiar voice and one approving word are enough to signal delight, irony or attraction, which keeps it in regular use across short-form video.