Misaki Sakimiya, known professionally as Zaki, serves as the deuteragonist of Dead Mount Death Play. She was originally the heiress to the Sakimiya Steel company, but her life took a violent turn after she witnessed the murder of her parents. Following that tragedy, she lived in an orphanage and eventually became a hitwoman who specialized in killing other assassins and gangsters, taking on the nickname Killer Killer. Her initial motivation was revenge against the man who killed her parents and others like him, but over time she discovered a genuine, brutal joy in her work. After completing a contract to kill Polka Shinoyama, she planned to end her own life, believing that suicide was the only kind of kill she had not yet experienced. However, she was herself murdered shortly afterward, then revived as a zombie by the reincarnated Corpse God who now inhabited Polka’s body. She later evolved into a vampire, gaining enhanced physical abilities. Despite her cheerful and high-spirited outward appearance—often seen as a carefree schoolgirl with long braided hair and glasses—she harbors a sociopathic and remorseless nature beneath the surface. Her role in the story shifts from antagonist to loyal ally and protector. She becomes a front-desk worker at a fortune-teller shop and serves as the physical combat specialist within the trio that includes the Corpse God, who handles mystical and necromantic matters, and Takumi Kuruya, who provides technological and intelligence support. As the story progresses, Misaki develops a strong sense of loyalty toward the Corpse God and her new companions, though she retains her lethal instincts and lack of hesitation in violence. Her notable abilities include expert hand-to-hand combat, the capacity to see spirits, and vampiric physiology that grants superhuman strength, speed, and regeneration.