Based on Charles Perrault's Puss in Boots, Pero is an anthropomorphic cat declared an outlaw by feline society. His rebellion—protecting mice, defying the natural order—forces him into exile while pursued by royal assassins, establishing his core trait of challenging conventions.

During travels, Pero forms a significant partnership with Pierre, a destitute miller's son. He devises plans to elevate Pierre's social standing, notably orchestrating a scheme to woo Princess Rosa, showcasing his cleverness and loyalty. When threats like the ogre sorcerer Lucifer endanger the kingdom, Pero shifts from self-interest to actively defending others against oppression.

Subsequently, Pero engages in high-stakes endeavors, accepting a wager with the wealthy Grummon to circumnavigate the globe within 80 days, risking permanent enslavement upon failure. Accompanied by companions like the hippopotamus Kato and Small Mouse, he faces deliberate sabotage attempts by Grummon throughout the journey, demonstrating his adventurous spirit and persistence.

Across different settings—including a Western-themed adventure titled *The Three Musketeers in Boots*—Pero consistently displays resourcefulness and protective instincts. Adopting the alias Ringo in one incarnation, he maintains his trademark trickery and swashbuckling approach, aiding vulnerable characters like Annie and Jimmy. Later confrontations involve adversaries such as Dr. Garigari.

Pero's personality remains marked by optimism, quick thinking, and roguish charm. His actions consistently prioritize helping the oppressed, liberating enslaved mice or thwarting corrupt figures. This enduring characterization as a noble outlaw solidified his status as Toei Animation's corporate mascot, with his likeness featured in studio logos since the film's 1969 debut.