Majikaja, also known as Kaja, is a Narehate living in the Village of Iruburu in the Abyss's sixth layer. Their true form is gaseous, described as being made of "smells" or scents, requiring artificial containers instead of a biological body. Their primary container is a stitched fabric sack within a puppet-like structure. Majikaja employs multiple specialized containers: one for daily use, a streamlined "Speed Form" for rapid movement needing special fuel, and a large vehicle-like form capable of transporting several people.

Exhibiting a consistently helpful and friendly demeanor, Majikaja often acts as a guide and interpreter for newcomers. They communicate using human speech, though they sometimes struggle with vocabulary and refer to themselves in the third person. Scent is a major focus; they frequently comment on the odors of others and their surroundings. Majikaja strictly adheres to Iruburu's value-based economy, emphasizing fair trade and equal exchange in all interactions.

Unlike many original villagers, Majikaja arrived after Iruburu's founding by the Ganja group. Their Narehate transformation resulted from "the desire to have a body that can move freely," having initially lacked mobility upon reaching the village. They learned Iruburu's history through conversations, including serious talks while drinking with original Ganja members.

Majikaja serves as the initial guide for Riko, Reg, and Nanachi upon their entry into the sixth layer. They lead the group to Poriyon, who is refining Prushka into a White Whistle, and subsequently give a village tour. During this tour, Majikaja explains local customs like the Balancing mechanism and inadvertently reveals critical information to Nanachi: that the sage Belaf possesses Mitty. This revelation directly leads to Nanachi trading themselves to Belaf.

Demonstrating loyalty, Majikaja intervenes to prevent Riko from making a disastrous trade with Belaf and later collaborates with her against the Fuzosheppu threat. Using Riko's hair as traded "value," Majikaja activates their Speed Form, enabling Riko to lure the creature into a trap. After negotiations with Faputa collapse and the attack on Iruburu begins, Majikaja uses their large container form to transport survivors, including Riko's group. When this container becomes immobilized during the village's destruction, Majikaja fulfills Faputa's final request to protect the group by abandoning their container. Their gaseous true form enters Faputa's unconscious body, temporarily taking control to shield everyone from falling debris. This act of possession, performed without proper merging procedures, results in Majikaja's demise as the village collapses.