Sultan's Legacy (The Jinni and the Isekai, #5‪)‬

The isekai Shiro and his jinni companion Jessamine must concern themselves with the war in the south—a war the Abassir Empire has been secretly losing. For Shiro, terrible events that may come to pass have in a way legitimized the previous sultan’s rule in some regards. Having killed Darius, mistake or no, Shiro and his friends now shoulder the burden and fate of a colossal empire.