The chant comes from Nico Yazawa in Love Live School Idol Project, the idol anime that began in 2013, where she uses Nico Nico Nii as her playful self-introduction. Fans clipped the line, shared it in anime edits and reaction videos, and turned its pose and rhythm into a recognisable meme beyond the show itself. Like other anime catchphrases, it spread because it is short, quotable and instantly tied to one confident character. It remains popular with Love Live fans and creators who want a cute, energetic burst of idol personality.