Following Ken Kaneki’s defeat by CCG investigator Kishou Arima during the Anteiku raid, the identity of Haise Sasaki emerged due to Kaneki’s severe brain damage and memory repression, suppressing his past experiences and personality. Physically, he displayed black hair with white streaks originating from the crown, though his hair gradually reverted to solid black over time. He typically wore standard CCG investigator attire, including a white trench coat, and utilized reading glasses. As a First Class Investigator, he mentored the Quinx Squad—a specialized unit of artificial half-ghouls implanted with Kagune-producing organs, comprising Kuki Urie, Tooru Mutsuki, Ginshi Shirazu, and Saiko Yonebayashi. His leadership prioritized teamwork and minimizing unnecessary ghoul casualties, reflecting a gentler demeanor than his former self. Reserved and cooperative, he habitually scratched his head when uneasy and employed wordplay in conversations. He maintained a preference for reading but harbored a strong aversion to tragic literature, contrasting with Kaneki’s tastes. Despite amnesia, fragments of Kaneki’s memories surfaced during high-stress situations as intrusive visions or emotional triggers, often involving past figures like Touka Kirishima or Hinami Fueguchi, causing psychological distress. The Red Spider Lily, symbolizing lost memory and rebirth, recurred as a motif during these fragments, underscoring suppressed trauma. Internally, he feared losing his CCG life and relationships, especially his familial bond with the Quinx Squad. Key events accelerated his reversion to Kaneki. Interactions with Shuu Tsukiyama and Kanae von Rosewald during the Tsukiyama Extermination Operation triggered a full resurgence of his memories, culminating in a helipad battle where he reclaimed his original identity and discarded the Haise persona. Post-reversion, his hair turned white, his eyes developed red sclerae, and reptilian scales covered his arms. He adopted a black trench coat and red gloves, severing ties with the CCG. As an artificial one-eyed ghoul, his Rinkaku Kagune possessed an RC level of 2753, rated SS. His kakuja abilities evolved throughout his journey, later enabling his transformation into the Dragon entity. After merging his Haise and Kaneki identities, he formed the organization Goat to bridge human-ghoul conflicts, reconciling his past and present selves.