Izanami studied at Jaula Blanca Institute alongside Koku and Yuna, forging a devoted friendship with Koku that later twisted into jealousy as Koku grew closer to Yuna. During the fire that destroyed the institute, they witnessed Minatsuki stab Professor Heath Kazama Flick ("Canopus") without intervening. Encountering the dying professor on the stairs, they pledged to protect Koku.

After the institute's destruction, Izanami joined the organization Market Maker alongside Minatsuki, serving as a subordinate. Years later, they resurfaced at a charity gala, luring Koku to a rooftop confrontation. During the ensuing chase, they revealed knowledge of Koku's self-suppressed memories and voiced lingering resentment over not being chosen.

This conflict climaxed at Lake Lenan, where Izanami taunted Koku about his locked memories and declared they would never forgive his rejection. Severely wounded, they instructed Koku to take their left leg for future use and urged him to "touch Canopus" to find Yuna before appearing to succumb.

Izanami survived, acquiring a new prosthetic left leg and later defecting from Market Maker. They aided Koku and Lily by sniping at Asagiri's car to disrupt a pursuit and helped safeguard the King. Reuniting with Koku, Lily, and Yuna, they assisted in reaching safety, plotting against Kirisame, and rescuing Keith Flick.

Izanami displayed light pink hair and clown makeup evoking Market Maker's logo. Their attire included a black jacket over an unbuttoned white dress with multicolored buttons, black gloves, and non-matching striped socks. They spoke dramatically and poetically, balancing playfulness with seriousness, often employing skateboard-based attacks. References used they/them pronouns.

Their name and sacrifice of their leg reference the Japanese goddess Izanami-no-Mikoto, echoing mythological motifs of power-bestowing sacrifice from the Jet-Black Epitaph legend. The blade within the prosthetic leg they gave Koku ultimately helped end Minatsuki's ambitions.