Tanuki Shigaraki

was a researcher of Root.

Background
Sometime after joining Root, Tanuki eventually became one of Danzō Shimura's most trusted followers. For one of his projects, he was put in charge of researching Hashirama Senju's cells to create Gozu Tennō — an ultimate weapon to further Root's own form of peace and order. Years later, when Danzō was killed, this resulted in Root being fully disbanded. The subsequent investigation of the division forced Tanuki to abandon his work, at least officially. After the existence of Root and its doings became public knowledge, its members became ostracized by the village. This indirectly led to his wife dying from failing health and sorrow at her despised status. This, along with feeling that Konohagakure had betrayed him, made Tanuki despise the village and he continued his work with the hope of "avenging" Root. Eventually, he completed his work, creating the Nue. He also trained his daughter, Sumire, into a capable ninja with the full knowledge of Gozu Tennō. He died passing on the summoning contract to Sumire.

Personality
Tanuki was a true believer of the teachings that Root enforced. Believing in the mantra of using any means necessary to complete his mission, Tanuki was a driven and single-minded individual. Despite Root's nature of no emotional attachment, however, this did not stop Tanuki from having a family.

After Danzō was killed and Root was disbanded, Tanuki became disenchanted with Konohagakure. Blaming the village for the fall of Root, he abandoned all ties to Konoha. Driven by revenge, he dedicated the remaining years of his life to completing his project and entrusted his hopes for it to his daughter.

Appearance
Tanuki was a tall man of a light complexion with shaggy black hair. He had a narrow jawline with pronounced cheekbones and face stubble. He wore a black kimono.

Abilities
While his skills are largely unknown, Danzō's utmost faith in Tanuki strongly implies that he was a very capable individual. As a scientific researcher, Tanuki was very intelligent, having been capable of creating a powerful beast from the First Hokage's cells, almost entirely on his own. He was also a very methodical and strategic man, having spent years training his daughter and eventually passing on the mantle of his revenge, in case he could not carry it out himself. He was apparently very skilled in fūinjutsu, having placed the formula for Gozu Tennō on his daughter.

Legacy
Even after his death, Tanuki's rage towards Konohagakure seemed to remain, as his loyal daughter Sumire chose to finish his revenge plan. However, Sumire grew to enjoy her peers in the Academy, and turned herself in. Instead, Tanuki's research was found and given to Sasuke Uchiha, who used it to further his own research.

Trivia

 * Like fellow Boruto: Naruto Next Generations villains the Mujina Bandits and their leader Shojoji, Tanuki's name is a reference to shapeshifting yokai from Japanese folklore: the tanuki, or "raccoon dog".