A cold-blooded killer in the Mugai-ryū. He's responsible for the death of Magatsu Taito's close friend, O-Ren. Shira's a sadistic psychopath who derives sexual pleasure in the torture and murder of his victims, particularly young women. After an attempt to ambush Anotsu goes horribly wrong and he tries to take it out on his attackers. He uses the saw-blade side of his sword to hack of some of their limbs, and then tries to rape a prostitute that was with them while cutting her up at the same time. Rin tries to stop him but is slapped away, Manji arrives and manages to take off Shira's hand before he runs off. Following this incident he cuts some flesh from his injured arm, and sharpens the bones into spikes. His hair turns stark white due to the trauma he caused himself. He develops an obsession with revenge on Manji which leads to him betraying his Mugai-ryū comrades, causing the death of Shinriji. Later, his quest for revenge against Manji leads to a battle with Magatsu Taito, who was traveling with Manji specifically so he could find Shira. This battle further cripples him with in the loss of his remaining hand. Recently he's been shown to be imprisoned in the same prison Manji is currently being held in, and has been set parameters/lists as to whom he shall face before being allowed to fight Manji (this list includes Magatsu). He also states that he has since lost one eye, and has a new "weapon" of sorts. This new weapon is actually Manji's lost arm. He now has the bloodworms as well. He uses a ninja-to sword, with a saw edge on one side of the blade. He usually uses the regular side to immobilize opponents by cutting off their legs, and then uses the saw-blade to cut off other parts of the body and cause maximum pain. This sword is named "Hotosogi" or woman shadow eraser. However, there is a second meaning for "Hotosogi" which also fits Shira's sadistic nature; when the kanji for woman and shadow are used together they become vagina. He first appears in Dark Shadows part 2 and is first named in Dark Shadows part 3.

(Source: Wikipedia)