Mokou is a Japanese game streamer known for loud, angry reactions during play, and clips of him losing his temper are widely reposted as reaction sounds. The phrase ao koura means blue shell, the Mario Kart item that homes in on the race leader and almost guarantees a crash. Fans tag clips like this with how to anger Mokou because triggering that reaction became a running joke. The clip spread on soundboards as a compact gaming rage sound.