Let's Buy the Land and Cultivate It in a Different World (Manga) Vol. 3

Astares of Chaos, a former member of the Four Heavenly Kings of the Demon Lord's army, has been ousted due to her embarrassing defeat to Kidan. Or has she? When the Demon Lord, Zedan, finds out that she's been kicked out, he immediately travels to challenge Kidan for the right to take her back. But Plattie has a better idea! The same one that made her so happy: If you can't beat 'em, marry 'em!