Kuehiko Roshihara is an anthropomorphic Russian Blue cat with grey fur and petrol-colored eyes. He maintains a consistently pessimistic and stoic demeanor, forming a direct contrast to his energetic work partner, Tapio Chatorazawa. As a college student, he undertakes various part-time jobs alongside Tapio during the initial season, including package delivery, restaurant service, window washing, retail positions at anime stores, and car rental assistance.

Their dynamic shifts significantly in the second season, evolving from temporary coworkers to genuine friends. Kuehiko gradually opens up to Tapio's persistent companionship, demonstrating subtle but meaningful growth in their relationship. This includes reciprocating past kindnesses and participating in personal activities outside work, such as meeting Tapio's family. While his reserved nature persists, he displays increased tolerance and occasional quiet appreciation for Tapio's exuberance.

Kuehiko's background involves a strict family environment, revealed when introducing Tapio to his household; this upbringing may contribute to his initially closed-off personality. His mother, also an anthropomorphic cat, appears in the series.

His second-season job experiences expand to encompass subtitle creation, locksmithing, construction labor, and children's stage performance. These roles often highlight his composed approach against Tapio's impulsiveness. While generally serious, moments of dry humor or faint amusement occasionally surface during their shared tasks.

Beyond work, his college life involves classmates like Hachitani and Nezaen, featured in a spinoff manga focusing on their academic experiences; his interactions within this setting remain largely unexplored in the main anime.

Kuehiko's journey reflects a gradual softening from aloofness to accepting deep friendship, marked by small but significant actions. He remains fundamentally reserved, yet his bond with Tapio becomes a defining aspect of his character progression.