Aoi Futaba, a seemingly shy high school student with glasses and a timid air, shares a quiet classroom with Kio Kakazu. Her reserved exterior conceals a sharp intellect and a mutual passion for obscure action films, which she timidly nurtures by lending Kio her personal collection. Behind this unassuming facade lies Momiji, a merciless assassin feared in the underworld as the "Messenger of Misfortune."

Her academic routine masks a clandestine career fueled by lethal combat expertise, mastery of advanced technology, and a high-tech battlesuit, *Nanashiki*. She operates a modified Ford Shelby GT500 rigged with tactical gadgets—net launchers, smoke cannons—and wields the unique ability to teleport objects within 50 meters via the command *Aportsu*, summoning weapons or gear instantly.

Disowned by her family for her teleportation power, Aoi navigates solitude beneath her professional ruthlessness. Though she executes missions with icy precision, she grapples with unspoken loneliness and a fledgling romantic attraction to Kio, expressed through awkward overtures: shared film discussions, homemade meals, and tentative holiday invitations. Seeking guidance, she strikes a pact with Manami, Kio’s childhood friend, trading espionage lessons for advice on femininity—a bargain that falters, leaving her bond with Kio anchored in their cinematic camaraderie.

The duality of her existence strains her psyche. As Momiji, she projects clinical detachment, yet flickers of fragility emerge—envy toward Eris’s confidence, stifled admissions of affection for Kio. These fractures in her armor underscore the clash between her bloodstained vocation and an aching, unfulfilled longing for ordinary human ties.