Fubuki Kai is a self-made ninja who relentlessly pursues surpassing her rival, Miko Mido, to prove herself the rightful leader of the Miroku ninja clan and claim the headmaster title. Following a defeat by Miko in a sexual duel, Fubuki undergoes a complete metamorphosis after being adopted by the Shikima, a demon race. She transforms into one of them to gain power comparable to Miko's. This transformation fulfills her desire for greater strength while altering her dynamic with Miko.

As a Shikima, Fubuki embraces her new demonic form and the enhanced abilities it provides. Her personality retains a provocative edge; she frequently irritates Miko by demonstrating superiority in their interactions, despite their newfound alliance. This establishes her as both a former adversary and a complex ally within the narrative.

Fubuki's Shikima physical appearance reflects her demonic nature, characterized by grotesque, irregular features typical of her race. Her role expands beyond personal rivalry, involving her in broader conflicts within the Shikima Realm and the ongoing battles between ninja clans.

Her development involves adapting to her demonic identity while navigating complex relationships, especially with Miko. This evolution from rival to Shikima-aligned figure highlights her relentless pursuit of power and recognition, marking her as an enduring and transformative presence.