The four-year old cat that Yumi Hayakawa owns in Cat Paradise, Kansuke was orginally saved from being hit by a van after Yumi came back and protected him. He bears a scar from being hit by her bike on his head, and transforms into a anthropomorphic human from Yumi's powers.
Kansuke's origin is revealed when the fox demon, Tsukumo Isshu, attacked Yumi and her friend. He remembers the day he met Yumi who tried to shield him (he was bleeding on the road) from a car.
Kansuke is created by Yuuji Iwahara; he has no current information regarding any inspiration used to create him. He first appears in Cat Paradise volume 1. His Drama CD's Japanese voice actor is Yuki Tai.
On the way to the Matabi Academy, Kansuke struggles to get out from Yumi's suitcase. He hisses at her for cramming him into the suitcase and dressing him in ridiculous clothes. While Yumi is attending her opening ceremony, Kansuke sees a glimpse of Princess Futakago and Shirayuki (her cat). He explores the school and finds a bunch of cats and Masashimaru, the boss. They fight because Masashimaru wants to teach who is the top cat.
During the rain, Tsukumo Isshu awakens and interrupts Kansuke's fight by attacking Yumi and her friend. Kansuke attacks the fox demon only to be fended off. He and Yumi stay in the shed. Kansuke remembers his past when he first met Yumi. He wishes to protect her, and that wish is answered by Princess Futakago and Shirayuki. The princess bestows upon Kansuke and Yumi, crests shaped like a crescent. Kansuke transform into a humanoid being and defeats the fox demon with one blow. He faints after the fight and reverts back into a cat.
After the event, Sakura, Akifuji's cat leads Kansuke to the library where Yumi and Akifuji are. Akifuji and Sakura explain the orign behind Kaen, the spirit beast. Kansuke does not believe their story. Akifuji leads them downstairs to the Kaen's seal is. The big boulder is cracked. Later at the park where Yumi and Kotobori talked about prophecies, Tsukumo attacks them. Kotobori and Masashimaru fend off Tsukumo's boar, and Shin kills the boar.