Masaru Sukegawa is one of the prisoners in Sector G. He is also a deadman with the power to create bramble weapons.
Masaru Sakegawa was an office worker in Japan trying to live an ordinary life after the Great Tokyo Earthquake. However, he kept secret that he was a closet homosexual from people and had a lover. Word gets out that Sukegawa leads an alternative lifestyle and begins to become ostracized at his office. He laments about his position and tries to confide in his partner about what is going on. Instead, he comes home one day to find his partner having sex with a prostitute. Sukegawa begins to break down as the woman mocks him and his partner chastises him for it as well. During his mental anguish, he cuts his hands and pushes the prostitute, unleashing his abilities as a deadman and killing the woman. It is because of this crime that he is imprisoned in Deadman Wonderland.
While in Deadman Wonderland, he begins to get in touch with his feminine side as he grows out his hair and dyes it. Sukegawa also begins to dress more like a woman and act like one too. It is because of this transformation that he is given the name Peacock by the higher ups of the prison.