Subuwu is a portmanteau of Subaru and uwu, the emoticon and voice style used online in anime meme culture to sound cute and exaggeratedly soft. The phrase is that a Subuwu became a meme caption for Subaru cars, especially Impreza and WRX models shared in car spotting posts. As the joke spread on social media and soundboards, creators started using the spoken version as a standalone reaction, separating it from any single video. It remains popular because the pun is easy to understand and works even without context.