Rina Nakayama

Seventeen-year-old Nanaka Kirisato is a high school student serious about her studies and goals in life. She frequently criticizes her best friend, Nenji Nagihara, for being a childish delinquent who spends his time fighting other boys. Then one day, after a heated argument with Nenji, she falls off a flight of stairs and suffers a brain injury, resulting in her mind reverting to that of a six-year-old. With this in mind, Nanaka's father and Nenji must keep her injury a secret as she struggles to live a normal life and grow up all over again.

The series focuses on PaRappa, a cute and happy dog who enjoys music and dancing and often spends time with his friends PJ Berri, Katy Kat, and the girl of his dreams, Sunny Funny. Along with various characters who make returning appearances from the video games, the anime introduces several new characters who are exclusive to the TV series. These include Matt Major, PJ's friend from Club Fun, Paula Fox, Sunny's friend who was rivals with Katy, Pinto, PaRappa's little sister, and Gaster and Groober, a villainous duo who cause all sorts of mischief.