Yukiko Tatsumiya, daughter of Yukari Tatsumiya, emerged from a traumatic birth shaped by supernatural forces and familial strife. Her existence stemmed from a non-consensual union between Yukari and her brother Yoichiro, though dark magic orchestrated by Yasunori Kato initially obscured her parentage. Kato, manipulating Yukari into a mystical pregnancy, falsely positioned himself as her father, later fixating on Yukiko as a vessel to resurrect Taira no Masakado’s vengeful spirit, coveting her inherited spiritual potency.

Manifesting psychic abilities in childhood, Yukiko became a pawn in Kato’s schemes. At fourteen, he abducted her to harness her connection to Masakado, an act that unraveled her true lineage. The revelation fractured her bond with Yoichiro, whose guilt-driven hostility clashed with her search for identity.

As a spiritual conduit, Yukiko stood at the nexus of disasters. Kato’s tampering with the Underground Dragon’s energy veins incited the 1923 Great Kanto Earthquake. Years later, he nearly sacrificed her to magnify the dragon’s rampage, thwarted only by Keiko Tatsumiya’s intervention and the robot Gakutensoku’s sacrificial act.

Her journey wove vulnerability with resilience. Confronting her origins, she bore the scars of her lineage while evading Kato’s relentless pursuit. Her dynamic with Yukari inverted at times, as her mother’s instability forced Yukiko into an unexpected caretaker role.

In Tokyo’s reconstruction era, her ancestry as Masakado’s descendant rendered her both a linchpin and a pawn. Though entangled in efforts to dismantle Kato’s plots, external forces persistently eclipsed her autonomy, binding her fate to the city’s supernatural reckonings.