Jibanyan was originally a normal red cat named Rudy who lived with a teenage girl called Amy. After being run over by a truck, he died and was reborn as a cat-like Yo-kai, taking the name Jibanyan. His motivation is deeply tied to this past event. Amy was devastated by his death and called it "lame," a word Jibanyan misunderstood as an insult toward his failure to avoid the truck. This drives his obsession with becoming stronger to defeat any vehicle he encounters, as he believes this would make Amy proud.

In the present, Jibanyan is a loyal friend and one of the primary Yo-kai companions of the main human character, Nate. He resides at Nate's house and is often summoned to use his combat abilities against troublesome Yo-kai. His personality is a blend of mischievousness, laziness, and determination. While he can be forgetful and childish, he is also fiercely protective of his friends and quick to take action when they are in danger. He has a well-known rivalry with passing trucks, which he attacks on sight, though this often results in him getting hurt and needing assistance.

Several key traits define his everyday behavior. Jibanyan has a powerful addiction to Chocobars, a type of chocolate snack, and is an avid fan of the fictional pop group Next HarMEOWny. He also has the ability to inspirit humans, which he originally used to force them to fight trucks for him, though he largely abandons this practice after befriending Nate. Among his fellow Yo-kai, he has a close but bickering relationship with Whisper, Nate's other constant companion; despite their arguments, they are good friends and can even fuse together to become a more powerful being named Buchinyan.

Within the story, Jibanyan serves as a primary fighter and source of comic relief. He is often the first Yo-kai Nate summons to resolve a conflict, relying on his signature move, Paws of Fury, a rapid series of punches. He possesses fire-based techniques and an ability called Adrenaline, which increases his power as he defeats opponents. His character undergoes notable development when he is given a chance to change the past. Confronted by the Yo-kai Kin and Gin, he learns that fate originally intended for Amy to die in the traffic accident instead of him. When given the opportunity to alter this outcome, Jibanyan refuses, choosing to save Amy's life by pushing her out of the way, sacrificing himself again to ensure she can live and pursue her dream of becoming a fashion designer.

In the later series, Yo-kai Watch Shadowside, which takes place thirty years after the original events, Jibanyan appears in a significantly altered form. This version is taller, more muscular, and possesses a much more standoffish and tough-guy personality. He has lost his memories of the past, including his connection to Amy. He continues to fight against trucks and love chocolate without fully remembering why. He becomes a companion to Nate's daughter, Natsume, and serves as her most powerful ally in battle. His lost memories are eventually restored when he meets Miho, Amy's daughter. This reunion briefly reverts him to his original, cuter form before he returns to his more hardened Shadowside appearance. This older Jibanyan, while gruff and often apathetic, retains a heart of gold, going out of his way to protect innocent people and animals from harm.