Romelia Senki: Hakushaku Reijou, Maou o Taoshita Ato mo Jinrui Yabasou dakara Guntai Soshiki Suru

From Seven Seas:
After journeying alongside her fiancé on his quest to defeat the Demon King, Romelia is suddenly deemed useless and sent home, her engagement annulled. While the prince and his group return as celebrated heroes, Rome goes home as a disgrace. But she’s not the same girl who left her province. While following the adventurers, Rome was the only one without magic or strength but she found her own abilities in trade, negotiation, finances, and gathering information. And now, she plans to use these skills to not only help her family’s province, but help the still struggling kingdom. The Demon King may be defeated, but his allies and demons continue to roam. With only her wits and brilliance, Rome will build an army of her own and keep the kingdom safe no matter what it takes.