In the aftermath of the events in 'Kite', the enigmatic killer Sawa vanishes following her quest for vengeance against her parents' killers. Years later, a mysterious figure glides through the shadows of a sprawling metropolis, embodying an angel of death who elegantly dispatches her targets before vanishing without a trace. Meanwhile, Monaka, a seemingly ordinary high school student, harbors a hidden alter ego as an angel of death, blending the realms of light and darkness within her own existence.