Two assassins face off at a certain "workplace." The cool bounty hunter Chateau and the mysterious and powerful Ryang-Ha.

Chateau and Ryang-Ha become enemies after this fight—at least, they should have, but for some reason Ryang-Ha takes a liking to Chateau and begins following her around.

Little by little, Chateau develops a cooperative partnership with Ryang-Ha, which gets her caught up in the struggle against the organizations hunting him down. Furthermore, that battle is related to her past as well.

Why did Ryang-Ha approach Chateau? What is Chateau's secret past? Two mismatched assassins weave together a twisted "Assassin X Assassin" thriller.

The strange gears of fate begin to move.

[Source: Crunchyroll]