Saltherine Aldarake, called Sally, begins as a sheltered princess whose kingdom falls to oni invaders. Rescued by Mikoto Kibitsu—a vengeful warrior skilled in slaying ogres—she sheds her royal identity by cutting her hair, vowing to seek coexistence between humans, demihumans, and oni. Driven by curiosity and empathy, her quest unfolds through fractured memories and encounters.

A peach-shaped sigil fuels Sally’s mysterious power, granting superhuman strength and immunity to oni assaults. Her eyes blaze crimson in battle, yet she wrestles to control surges of raw energy, which sometimes trigger violent outbursts. This immunity baffles adversaries like Sumeragi, a high-ranking oni who endures her strikes. Unlike Mikoto’s disciplined mastery, Sally’s abilities remain volatile, mirroring her inner turmoil.

Guided by compassion, Sally champions redemption for even former foes like Carrot, an oni with a bloodstained past, and bonds with Frau, a rabbit demihuman. Her idealism faces harsh tests: systemic bigotry, clashes between mercy and retribution, and dilemmas over when violence becomes necessary. A childhood octopus attack left lingering trauma, manifesting in vivid hallucinations during stress—a vulnerability contrasting her combat ferocity.

Hints of an artificial origin, akin to Mikoto’s guardian Hiko, linger unexplored. Her journey intertwines with enigmatic figures like Sumeragi, whose facade of peacekeeping obscures ambiguous motives, challenging Sally’s trust. The anime’s non-linear structure weaves her growth through disjointed fragments—her kingdom’s ruin, early encounters with Mikoto—echoing her fractured resolve and the chaotic path toward understanding coexistence.