Curtis is the younger brother of the protagonist Keroppi in the anime Kero Kero Keroppi no Christmas Eve no Okurimono. He is part of the Keroppi family, which consists of frog characters living near Donut Pond, and is known in some versions as Koroppi.

As Keroppi's brother, Curtis is portrayed as the youngest of the triplets in his family, which includes his brother Keroppi and his sister Pikki. Unlike his more adventurous and outgoing sibling, Curtis is characterized by a diligent and hardworking nature. He has a particular enthusiasm for mechanical things and working with his hands, demonstrating a practical and focused personality. He is also noted to be a capable singer.

In the story of the Christmas special, Curtis appears alongside his brother and their friends as they experience the magical events of Christmas Eve. While the central plot focuses on Keroppi finding a small star named Twinkle and helping her become a true Christmas star, Curtis participates in the group efforts to assist Twinkle. When Keroppi devises a plan to use a generator to help Twinkle light up and return to her place in the sky, Curtis is present with the other friends as they execute this plan and cheer on the little star's success.

His primary motivation is likely tied to his family and friends, as he works together with them to solve the problem of helping Twinkle. His role in the narrative is as a supporting character. He does not drive the main action but provides valuable assistance and contributes to the collaborative atmosphere of the group. His key relationship is with his brother, Keroppi, as well as with the broader circle of friends from Donut Pond. Development for Curtis is not a focus of this special; the narrative concentrates on the external adventure and the growth of the guest character, Twinkle. His notable abilities include his mechanical aptitude and his diligence, which prove useful in the group's task of rigging the generator to the Christmas tree.