Tokiko Shigusa is a mysterious woman with ties to a religious sect who frequents Ueno's slums. She possesses straight, waist-length black hair that obscures her eyes and a slim physique, standing 163 cm tall and weighing 44 kg. Her pale complexion and attire—often trench coats and garments adorned with ribbons—contribute to her unsettling aura. Her personality is gloomy, stoic, and deeply religious, reflecting her sect affiliation. Tokiko becomes a suspect in a series of brutal dismemberment murders plaguing Ueno, leading to her police custody. In the story's true ending, she dies by hanging under circumstances initially deemed suicide. This death is later revealed to be murder, orchestrated by Kozuki Yura and staged to mimic suicide. Her background involves significant involvement with the Senri cult and its activities, though her origins and personal history remain undisclosed. Her narrative role remains consistent across all official media adaptations.