TV-Series
Description
Kirika Ueno holds the dual roles of class representative and Student Council President at Haruaki Yachi's high school. Her connection to Cursed Tools, or Wathes, originates from her coerced involvement with a research organization founded by her older brother, referenced as Laboratory Emirate, Nightcrawlers, or Yamimagari Pakuaki's Lab Chief Nation. This group investigates the properties and mysteries of Cursed Tools, directing Kirika to observe Haruaki and his allies, specifically gathering intelligence on the Cursed Tool Fear Kubrick. Her forced participation creates significant emotional conflict due to the required deception and her loyalty to her friends.

Kirika wields two primary Cursed Tools. The first, Gimestorante’s Love (or Ginstrnag's Love), is a bondage-style leather outfit permanently fused to her body. Forged from the curses of a sadistic master and abused slaves, it grants Kirika immortality and mid-level regeneration, enabling her to survive and heal from fatal injuries like dismemberment, disembowelment, or decapitation. Healing speed depends on wound severity, with limb regrowth taking significantly longer. Removing the outfit would cause her immediate death. Her second tool, The River of Black Strings (or Tragic Black River/Kurokawa Karen), manifests as controllable, infinitely extendable black leather belts or straps. Once a serial killer's favored weapon, it can bind, crush bones, strip flesh, or act as a grappling hook. Its curse demands regular sacrificial victims to satisfy its murderous compulsion. To avoid harming others, Kirika directs its lethal force against herself, relying on Gimestorante’s Love to heal the self-inflicted injuries. This necessary ritual causes her deep shame, disgust towards her body, and emotional pain.

At school, Kirika maintains a reserved, dutiful, and serious demeanor, often perceived as strict or unapproachable, rarely showing overt emotions like smiles. Despite this, she values friendship and class unity, extending kindness to newcomers like Fear. She engages in a recurring cooking rivalry with Haruaki Yachi during lunch periods, judged by classmates. Kirika develops romantic feelings for Haruaki; his discovery of her Cursed Tools and self-harming rituals, followed by his unwavering acceptance, deepens their mutual trust and strengthens their relationship.

Her frequent catchphrase, "Absolutely ridiculous!" or "How foolish!", responds to absurd or challenging situations. In combat, Kirika relies on her Cursed Tools over innate physical prowess. The River of Black Strings enables attacks several meters away, powerful enough to break bones or tear flesh, though she often uses it for binding and restraint. Her regeneration and immortality compensate for otherwise human-level durability and speed, allowing her to endure grievous injuries. Later (volume 17), she temporarily loses The River of Black Strings and borrows the Cursed Tool Chupacabra Bandage, which functions similarly for binding and mobility but also stops bleeding by feeding on blood, causing intense pain. She eventually wields both tools simultaneously.