Shiwori Adachi works at a cosplay café, embodying a Rococo-era princess—a persona starkly at odds with her reserved true self. Her routine shifts when Taiju Nakano, a regular customer, draws her into a duel comparing their romantic partners’ spending habits. The stakes escalate under the Slave Control Method (SCM), a device binding the loser to the winner as a slave. Though Taiju initially seems eager to lose—presenting as female and feigning submission—their duel twists when a rival drugs Shiwori’s drink. Taiju retaliates violently, exposing his male identity, and claims victory by midnight, enslaving Shiwori.

Their arrangement unravels swiftly as Zenichi Bunkyou, another SCM user, ambushes them. He coerces Shiwori into a brutal physical duel, overpowering her and transferring her enslavement to himself. Determined to free her, Taiju allies with Julia Katsushika under a conditional pact: his own enslavement to Julia if they succeed. During the clash with Zenichi, an unexpected challenger intervenes—Zushiohmaru, a dog implanted with an SCM. The animal defeats Zenichi, severing Shiwori’s bondage and underscoring the chaotic unpredictability of SCM duels, where even non-human entities enforce involuntary servitude.

Shiwori’s role in these conflicts stems not from ambition but manipulation, casting her as a pawn within wider SCM user rivalries. Her personal history and aspirations remain veiled, her arc defined by reactive survival rather than agency. The aftermath of her liberation and her trajectory beyond these events are left unaddressed.