"Omae Gotoki ga Maou ni Kateru to Omou na" to Yuusha Party o Tsuihou Sareta node, Outo de Kimama ni Kurashitai THE COMIC

From Seven Seas: To vanquish the increasingly powerful Demon Lord, divine revelation ordained a party of heroes, each blessed with a unique power. That spelled trouble for Flum Apricot, a total weakling of a girl who has no idea what her power of “Reversal” even does. Betrayed and left behind with a wretched slave trader who enjoys nothing more than seeing his merchandise fight for their lives, Flum thinks all hope is lost until she gets her hand on a massive, cursed sword. Finally, after so many years, she understands the nature of her power, and both she and her new companion Milkit are about to experience a huge “Reversal” of their fate!