A Deadman nicknamed 'The Crow'. He has the ability to form blood into scythes and loves battling in the Carnival Corpse, making him very dangerous and one of the most famous Deadmen.
Edgy and always looking for a fight, Crow values strength above all. He is a powerful and trust worthy ally and a fearsome foe with a strong, albeit hidden, sense of justice and honor (a result of his past as a policeman). He has a odd aversion to beautiful women, especially their breasts, becoming flustered and awkward. Senji takes a liking to Ganta, despite the latter's size and occasionally meekness; he is often impressed at Ganta's stunts of pure will and determination.
Senji Kiyomasa was originally an officer of the law, trying to keep the piece after a devastating disaster hit humanity. However, a wanted criminal managed to kill the rest of his squad, and he was unjustly arrested and sentenced to the Deadman Wonderland.
The character of Senji Kiyomasa was conceptualized by writer Jinsei Kataoka and artist Kazuma Kondou of Eureka Seven fame.
While searching for the Red Man Ganta scouts through the secret G-Sector of Deadman Wonderland and finds a person who can control their blood, just like himslef and the Red Man. In blind fury Ganta attacks Crow and they get into a little struggle, ending with Ganta getting a lucky hit at his chest.
After they both get captured by staff and sent into the arcana Crow begins the match taking advantage of Ganta's inexperience but loses because of an close-quarters attack to his chest, still weak after the last fight.
Because he lost the fight, Crow was punished by having his right eye ripped out for further study. Despite this, he becomes friends with Ganta and even considers him a rival.
When Scar Chain including Ganta is about to be destroyed by the Undertaker C squad Crow jumps in to save Ganta unwilling to miss out on a fight with the undertakers back to back with him. Unknowingly he defeated the leaders within seconds of the fight.
Feeling underwhelmed he refuses to join Ganta in feeling happy in with how things are. He however agrees to train Ganta to fight as fast as him, seeing as his blade is fast enough for worm eater to be unaffected.
Like all the other major Deadmen, Crow received a mask meant to incite personal disdain and anger from the Crow. This pushing him and many other directly into a trap set by the promoter. Upset like the rest The Deadman Crew were put up against the Forgeries in a carnival Corpse meant to show the horrors of both the Deadman and the superiority of the Forgeries.
This However did not go as the promoter planned. The Deadmen with their combat experience and diversity of abilities the Deadman Crew were in the process of crushing the forgeries once and for all. Something the Crow as well as the other wanted badly.
This however also did not go as planned for the Deadman Crew. Ganta not wanting Azami to die, being one of the forgeries, destroyed the Carnival Corpse building itself, ending the fight in a bloody draw, this also lead to most of the Elite Deadmen being injured and sent to the med centers allowing the forgeries to go uncontested.
With Ganta, Shiro, and Azami cornered and attempting to shut down the promoters control over the Forgeries, A Team of elite Forgeries get in their way, however the rest of the Deadman Crew lead by the Crow join in to help Ganta get to the control center. Each Deadman then faced off with their opposite in single off fights.
The Crow versed off Akatsiki, one of the perfect forgeries. Akatsiki branch of sin is the ability to control his own blood the equivalent of super muscles, strong enough to snap the Crow claws with his hand, this power turns out a perfect match with crow, being one that keeps his blood in his body as opposed to Crows which require a large portion of his blood.
Akatsiki eventually tells Crow that he is partially responsible for the murder of the police in his unit driving the crow further, desiring revenge. Crow eventually wins by using almost all of his blood into a giant sword finally overcoming Akatsiki's Strength. This nearly kills the Crow, but he is victorious.
During the mission to destroy the Wretched Egg Ganta is taken by the mockingbird. The Crow goes after Ganta: The Woodpecker to rescue him from Toto: the mockingbird. He arrives in time to save Ganta from having Mockingbird take over Ganta. Knowing he can not win one to one against the Mockingbird, the Crow attempts to simply stall him enough to give Ganta the time to escape.
With the mocking bird literally ripping Crows arm off and beating him senseless the death the Crow seemed inevitable. Ganta however jumped into the fight saving the crow from death and turning the tables on the mockingbird.
The fight eventually reaches the top of deadman wonderland as the Crow/woodpecker team defeat the mockingbird by using the same strategy Ganta used on the woodpecker. The Crow slashed up the tower forcing him to turn his attention up, during that opening Ganta pops him point blank in the chest, and to add insult the misery, Crow slashes Mockingbirds arm and leg off. Ending the match with victory
Because he is a Deadman, Crow has the unique ability to alter his bloods shape into scythe blades, which is known as his Crow Claw attack. When he attacks at the speed of sound he is preforming his Invisible Black move. He also has the power to make a Giant Blade from his blood thought this cause him to use massive amount of of his blood putting himself at risk.
Deadman Wonderland: Red Knife Wielder (OVA)
An OVA that features Senji's past