Mayuri Kurotsuchi (涅 マユリ, Kurotsuchi Mayuri) is Captain of the 12th Division in the Gotei 13 and 2nd president of the Shinigami Research Institute. His lieutenant is Nemu Kurotsuchi, his artificially-created "daughter".
Mayuri Kurotsuchi is a researcher and personifies the stereotype of the mad scientist. By his early actions during the Ryoka Invasion, he is displayed as one of the most sadistic and cruel Shinigami. He sees everyone and everything not as a living being, but as an object to be researched—including himself.He has little respect or regard for most others, and was even willing to turn his own men (who were not aware of his plans) into living bombs in an attempt to capture Uryū Ishida and Orihime Inoue for experimentation.He also withheld vital information about the Bounts from the other Shinigami in order to capture one as a research subject for himself.
It is known that Mayuri's favorite food is pike fish, and that he does not like onion. One of his free-time activities is reading every character published in Seiretei Communication. He himself publishes a serialization in the journal, titled "Effective Medication for the Brain", which apparently contains detailed instructions on preparation of medicine and their application. Surprisingly, it is highly popular among the readers.
In battle, Mayuri likes to play with his opponent, torturing them little by little until they can hardly stand. This was shown in both the fight with Uryū and his Espada counterpart Szayel. Every time he fights he uses it as an experiment testing himself and his opponent little by little. He also uses it as an oppurtunity to implant microbes or other things in case they get away. Before engaging, though, he will make extensive research on his possible opponents to tilt the chance of winning in his favor.It is seen that, before the Winter War, he is busy reading in the library with a note on the door saying, "Enter and Die." He's shown to be doing this every time before he fights, against both the Bounts and the Espada.
Byakuya has slate gray eyes and long black hair, which he keeps up in intricate white headpieces called kenseikanthat symbolize his nobility as the head of the Kuchiki family, one on top of his head and another on the right side. He wears the standard captain uniform along with a white scarf made by the master weaver, Tsujishirō Kuroemon III. The scarf is made from the silver-white, windflower light silk (ginpaku kazahana no uzuginu) and is a family heirloom that is handed down from generation to generation and is given to each Kuchiki family head. The scarf alone is worth enough to buy ten mansions in the Seireitei.He also wears fingerless white tekko that cover only the back of his hands.
