Kyōka Izumi vs. Kōyō Ozaki

Kyōka Izumi vs. Kōyō Ozaki is a battle fought between former Port Mafia assassin Kyōka Izumi and Mafia executive Kōyō Ozaki before the outbreak of the three-way gifted organizational conflict among the Armed Detective Agency, the Mafia, and the Guild.

It happened somewhere in Yokohama's central square during the Mafia's operation to eradicate the Agency and Kōyō's personal attempt to retrieve Kyōka back to the Mafia.

Prologue
After Kōyō greatly injures Atsushi Nakajima by commanding Demon Snow and using Golden Demon, Kyōka accepts Kōyō's invitation to come with her in order to spare Atsushi from getting killed.

Battle
Kyōka turns out to have put on an act to conceal her killing intent and strikes Kōyō with her tantō, though the executive quickly catches sight of it and grasps the weapon, wounding her palm in the process. Kōyō compliments her move, while Kyōka reveals having swiped Kōyō's phone. Despite the latter asking her not to use it, Kyōka contacts her own phone to activate Demon Snow and order it to vanquish her opponent, resulting for the two phantoms to engage each other in combat.

Meanwhile, Kyōka and Kōyō are likewise locked in a duel using their blades, a feat that Kōyō remarks truly befits Kyōka's demon-like nature, but Kyōka immediately rejects it. Kōyō expresses her sympathy for her, being a "flower born in the darkness" herself who ends up getting scorched and reduced to ashes by the light in the past. She further persuades Kyōka that her nature meant for slaughter cannot ever change, reminding her that Demon Snow – the very weapon she uses to achieve her previous missions and objectives – killed her own parents.

Aftermath
At such retort, Kyōka drops the phone that dissipates Demon Snow. Various mafiosi also arrive at the central square, while Kōyō assures Kyōka that she shall never have to wield a blade for the sake of finding where she can belong if she returns back to the Mafia. The executive then approaches Kyōka and promises to protect her. As Kyōka drops her tantō, Kōyō instructs her men to dispose of Atsushi, though Agency members Doppo Kunikida and Kenji Miyazawa arrive to rescue him.

Manga and Anime Differences
The anime includes some subtle differences from the manga. In the anime, Kōyō further remarks that someone like Atsushi who lives in the world of light can never understand what happened after she reveals that Demon Snow slaughtered Kyōka's parents.

Moreover, while Kōyō simply places her arms around Kyōka's shoulders while leaving with her in the manga, the anime depicts Kōyō covering Kyōka's head and sight with her kimono sleeves even until Kunikida and Kenji arrive. This may be a symbolism of Kōyō not wanting to anymore expose Kyōka from the "light".