The phrase comes from Usada Pekora, a Japanese VTuber with Hololive known for peppering her speech with peko, inspired by her rabbit-girl character design. Fans clipped her rapid repetitions from livestreams and shared them across anime and VTuber communities, where the sound joined other short catchphrase clips like Tuturu as a reusable reaction. Its appeal lies in instant recognition for fans and pure cuteness for newcomers, so it keeps resurfacing in edits, soundboards and streams years after Pekora's 2019 debut.