Nabu from Ga-Rei-Zero refers to a pair of twin brothers collectively known as the Nabu Brothers. They are African shamans who serve as agents of the Supernatural Disaster Countermeasures Division, the same government agency that employs Yomi Isayama and Kagura Tsuchimiya. The brothers are identical in appearance, making it nearly impossible for their teammates to tell them apart. They share the same name, a cultural trait from their background for twins. In conversation, they frequently finish each other’s sentences.

As characters, the Nabu Brothers are loyal operatives who fight supernatural threats alongside their colleagues. Their motivations are professional and rooted in their duty to protect humanity from malevolent spirits. In the anime Ga-Rei-Zero, both brothers appear as supporting characters. One of them is killed during a mission by the villain Ranguren. The surviving brother continues to work with the division but later dies while attempting to protect Fujiko Mine during an attack by the Juugondō organization. This sacrifice highlights their sense of responsibility and willingness to lay down their lives for others.

Notable abilities stem from their shamanic heritage, which grants them spiritual awareness and the capacity to combat supernatural entities. However, specific details of their powers are not extensively elaborated in the series. Their role in the story is primarily that of background agents who contribute to the division’s operations and serve as examples of the broader team’s sacrifices. Relationships with main characters such as Yomi and Kagura are professional, with no deep personal development explored. The Nabu Brothers’ narrative serves to underscore the high cost of the ongoing conflict with supernatural forces.