Mukyu Isurugi serves among the Revisions, cybernetically augmented future entities surviving a pandemic by harvesting humans as biological resources. Her temporary humanoid guise sports canine ears, a tail, and a gothic lolita maid ensemble—a pragmatic design for human interaction, devoid of aesthetic consideration. This whimsical exterior clashes with her ruthless nature; she torments Shibuya’s inhabitants with sadistic relish while shielding her twin sister, Chiharu Isurugi, with unflinching devotion.

Ranked above Nicholas Satō within the Revisions’ hierarchy, Mukyu asserts dominance through relentless verbal and physical abuse, underscoring their strained dynamic. Her loyalty remains exclusively reserved for Chiharu, whose shared body symbolizes their symbiotic bond. Though the Revisions prioritize collective survival, Mukyu executes missions with a personal fervor, savoring clashes against Shibuya’s defenders.

The sisters’ temporary form, while superficially innocuous, functions as a deceptive interface for their lethal operations. Mukyu’s origins remain obscured beyond her identity as a Revisions operative, and her role remains static, anchored to the group’s objectives without expansion in supplemental narratives.