Isekai Mokushiroku Mynoghra - Hametsu no Bunmei de Hajimeru Sekai Seifuku

I reincarnated as an evil god. Ira Takuto succumbed to illness at a young age and ended up reincarnating in a world that resembled the strategy simulation game, 『Eternal Nations』, of which he loved playing when alive. What appeared in front of him was Atou, a girl belonging to the evil civilization that he used to play as,