Shinobi Shaw was the illegitimate son of Sebastian Shaw and a japanese woman. During his childhood, he'd sometimes attend the Hellfire Club's parties, where he got acquainted with Warren Worthington III (the future X-Man Angel), who also accompanied his father. Over time, however, the two grew apart.
At some point, Shaw became a member of the Upstarts, a group of young mutants organized by Gamesmaster that were competing to see who could kill more mutants. As part of this contest, Shinobi visited his father in Switzerland and killed him (or so he thought), thus inheriting his father's empire and his network of social and political connections, including his position as a leading member of the Hellfire Club's Inner Circle.
Shinobi attempted to revive the Hellfire Club's Inner Circle with his old friend Warren and his fellow X-Man Psylocke, but they refused his offer. Shaw's next contest with the Upstarts involved assassinating the surviving New Mutants and Hellions, but their plans were thwarted by the combined effort of X-Force and the New Warriors.
Although Shaw briefly managed to obtain the assistance of several mutant associates, his frequent violent conflicts with other superhumans ultimately resulted in his failure to establish himself as his father's successor. Once he learned that his father was still alive, Shaw, presumably in fear of retaliation for his assassination attempt, deserted all of his inherited positions and returned to a more secretive mode of life.
As a result of the Scarlet Witch's actions, nearly all of the mutants in the entire world were stripped of their powers, but Shinobi was among the 198 mutants cataloged to have retained their powers. Still, Shinobi was eventually killed by his father, but, along with many other deceased mutants, he was resurrected by Selene and Eli Bard with the Transmode Virus.
Years later, he rejoined the Upstarts, and together they killed the Nasty Boys. When the X-Men arrived to investigate the scene, Shinobi revealed that his actions were meant to protect the Nasty Boys from falling into Emma Frost's hands. Surrounded by the X-Men and unwilling to surrender, he simply phased his hand into his head and committed suicide.
Shinobi was again resurrected, this time by the Five in Krakoa, after his father requested them to do so. Sebastian wanted to reconnect with his son and make him the new Red King of the Hellfire Club, but, after Emma Frost (the White Queen) told him that she had already picked a Red Queen (Kate Pryde), he made Shinobi the Black Bishop instead.
Still, Sebastian didn't plan to share the reign of the throne with the two queens and secretly killed Kate, hoping the Five wouldn't be able to revive her. When Emma found out, she began planning her revenge on Sebastian, but first, she intended to make sure no one else was involved: she telepathically commanded Shinobi to meet her and probed his mind, but, after finding out he was ignorant to his father's plans, she let him go. It was later revealed that Sebastian was not his father but Harry Leland.
