Kafka is a calm, intelligent, and laid-back man in his early thirties. He serves as Umagon's bookkeeper. Unlike Gash's other friends, Tio and Kanchome, whose bookkeepers are celebrities, Kafka is an automobile engineer who moved from Germany to Japan, paralleling Umagon's journey from England to Japan.
Kafka first encounters Umagon when a dog snatches his book. He manages to calm the dog and retrieves the book, holding onto it until their paths cross again at the Devolo Ruins, where they face off against Dalmos. It is later uncovered that Kafka came to meet Umagon at the behest of Dr. Riddles, which clarifies the note he left for Kiyomaro detailing the location of Zofis' ruin-base.
During the Faudo arc, Kafka develops feelings for Elle Chivas.
Sunbeam adheres to a philosophy of being a "cool adult," and actions such as abandoning Umagon or his comrades go against his principles. This quickly earns him the trust and friendship of the others. He enjoys using the word "groovy" and frequently employs slang.
After the battle concludes, it is revealed that Kafka is living in Africa with Elle, presumably as a couple. There, they care for animals, and Kafka continues his work at a car company, which is thriving. Like all the other partners, he receives a postcard from his former partner Umagon, indicating that he is doing well.
