Chiyu 12-sai is the main character of 'Netrun-mon', an anime based on the Japanese internet culture magazine 'NetRunner'. Chiyu is depicted as a 12-year-old girl who originally appeared as a satirical character on a popular personal website. In the series, she represents the online persona of a young girl navigating the eccentric world of the internet. Chiyu is cheerful, quirky, and often finds herself in humorous and surreal situations, embodying the early 2000s Japanese internet subculture.