Tatsuya Katori, a man shaped by his father Kadono’s unjust downfall under corruption charges fabricated by Kamoshige Arimiya, navigates a labyrinth of vengeance and ambition. After Kadono’s death, Katori accepts a secretary role under Kamoshige, whose guilt-driven employment offer masks a desire for redemption. When Kamoshige dies abruptly from heart failure, Katori pivots from revenge to securing a locked safe holding the family’s inheritance—a goal entwined with Kamoshige’s widow, Sumire Arimiya. She compels him to extract the safe’s PIN by seducing her stepdaughters: skeptical Misora, guarded Chisato, and traumatized Shion.

Katori dissects each sister’s vulnerabilities. Misora, distrustful yet pragmatic, allies with him to thwart Sumire’s ascendancy, their calculated intimacy revealing clues about Chisato’s preferences. Chisato, entangled in a covert relationship with maid Emiri Kasai, resists until Katori weaponizes evidence of her coercing Emiri, forcing her compliance. Meanwhile, visions of Kamoshige’s memories expose his abuse of the sisters, particularly Shion, whose childhood trauma holds the key to the safe’s altered password.

Balancing manipulation with fleeting empathy, Katori apologizes for Kamoshige’s crimes even as he exploits the sisters’ wounds. His ascent from secretary to governor—and ultimately Arimiya Family head—hinges on strategic alliances, psychological coercion, and a cold mastery of secrets. He avoids brute force, preferring to dismantle adversaries through calculated exposure of weaknesses.

Though driven to dismantle Kamoshige’s legacy, Katori perpetuates its cycles of exploitation, oscillating between antagonist and protagonist. His motives blur vengeance, ambition, and a detached intrigue in the family’s fractured dynamics, culminating in his dominion over the Arimiya Tower—a triumph as methodical as it is morally ambiguous.