Nyanpasu is the signature greeting of Renge Miyauchi in Non Non Biyori, the slice-of-life anime based on Atto's manga that first aired in 2013. Renge uses the made-up word in place of a normal hello, and fans quickly picked it up as shorthand for her character. Clips of the line spread through anime forums, YouTube edits and short-form video, where it became a recognisable cue for cute, wholesome content. It remains popular because it is short, distinctive and instantly signals anime fandom without needing any explanation.