The phrase comes from Nekomata Okayu, a Japanese VTuber with Hololive JP, whose relaxed streams and food moments made her munching noises a fan favourite. Mogu mogu itself is a Japanese onomatopoeia for chewing, the sound of small, repeated bites, so the clip needs no translation to be understood. Fans have reused it in short edits, reaction videos and soundboards because it instantly signals eating in a gentle, playful way. Its short length also makes it easy to drop into memes without interrupting the scene around it.