The second season of Hyakushou Kizoku.

The second season of Kimi to Boku no Saigo no Senjou, Aruiwa Sekai ga Hajimaru Seisen. 
Iska guards Sisbell, sparking Alice's jealousy. Amid a conspiracy, can they thwart personal disputes and war? 
(Source: Crunchyroll News)

Two assassins face off. 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. Two mismatched assassins weave together a twisted "Assassin X Assassin" thriller. The strange gears of fate begin to move. 
 
(Source: Crunchyroll) 

Note: The first episode had an early premiere at AnimeNYC 2021.

Saltherine Aldarake, princess of the Kingdom of Aldarake, dreams of traveling the world—a dangerous dream in a land where monsters roam the countryside as they please, and humans live behind high, strong walls. But when a chance meeting with traveler Mikoto gives hope to her dream, he shatters it soon after, as he reveals himself to be none other than Momotaro, ruthless demon-slayer. Though horrified by the gore Momotaro leaves behind, Saltherine is convinced more than ever that she needs to learn about the world beyond her walls, and journeys out...following the steps of the mysterious, charismatic, terrifying boy she met that day...
 
(Source: Kodansha USA)

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