Hiyosu

is a department head in the Shinigami Research and Development Institute, which is tied to the 12th Division.

Character Outline
Hiyosu is a large, green Shinigami with a bulbous head and an extendible eyeball via a crank on his head. He was the one that originally discovered Rukia Kuchiki's unusual Gigai. Later, he is shown scolding Rin for scanning incorrectly when Soifon and Yoruichi Shihōin are investigating the Bounts. He was also present when the Research Institute discovered that Yammy Riyalgo and Ulquiorra Cifer had begun a small invasion on Karakura Town.

Hiyosu, along with the other members of the Research Institute, has also been known to perform field research when requested by his captain, Mayuri Kurotsuchi, as shown during the Beast Swords arc.

Trivia

 * He is one of the few Shinigami within the Gotei 13 who doesn't take on the appearance of a Human.


 * It is interesting to note that, in the anime, Hiyosu appears to alter the colour of his skin from green to white between the invasion of Ulquiorra and Yammy and the briefing of Rin Tsubokura prior to his assignment on Earth.