Yuusha-sama no Osananajimi to Iu Settei no Make Heroine ni Tensei Shita no de, Chougou-shi ni Job Change Shimasu.

As a monster's fangs close in, a sudden realization strikes. This terrifying moment is not unfamiliar—it is a scene from an RPG played in a past life. Reborn into that very game world, the protagonist discovers she has been cast as the hero's childhood friend, a character destined to become the ultimate losing heroine. In the original story, her role ends barely an hour into the opening when she confesses her feelings just as the hero departs on his grand adventure. Players always pitied her, knowing he would soon meet another girl who would cling to him throughout his journey while she was left behind. Refusing to accept this tragic fate of being abandoned in her quiet village, she resolves to completely rewrite her destiny. When a unique ability for compounding suddenly awakens within her, she abandons the predetermined script entirely. Her new goal is to leave home and travel to the royal capital to change her class and become an alchemist. She has no interest in playing the part of the hero's forgotten childhood companion. Instead of waiting for a doomed romance, she intends to forge her own path and seize happiness with her own two hands.