Yajuu Senpai, also written as Beast Senpai in English searches, became a long-running figure in Japanese online meme culture under the nickname 810, a number pun on his name. His Yarimasu Ne catchphrase was clipped, remixed, and reused across Nico Nico Douga style MAD videos and later short-form edits far beyond its original context. The phrase roughly conveys impressed approval, which helped the sound travel even to viewers who do not speak Japanese. It remains popular because the short delivery works as a standalone reaction.