Okiraku Ryoushu No Tanoshii Ryouchi Bouei Raw Manga Best ((install)) Info

The story follows a protagonist who isn't your typical hot-headed shonen hero. Having inherited or been transported into the body of a minor noble, he discovers his territory is weak, poor, and surrounded by hostile neighbors. Instead of panicking, he uses modern knowledge (tactics, economics, engineering) and a laid-back philosophy to fortify his lands.