The Frontier Lord Begins with Zero Subjects: Tales of Blue Dias and the Onikin Alna Vol 2

From the J-Novel Club edition

Dias is getting used to life on the plains with his new wife—er, fiancée—Alna, and they even have actual subjects now: Dias’s old war buddy Klaus, and a group of refugees fleeing a civil uprising in the neighboring Kasdesk domain. Dias is desperate to raise the population in Nezrose without resorting to slavery, but he’s about to get a visit from none other than the lord of the Kasdesk domain himself, an infamous womanizer always accompanied by a harem of slaves. Dias will soon learn that as on the battlefield, politics and diplomacy is all about seeing who’s friend or foe.

Source: Yen Press