“Soooorry. Turns out we don’t need you in the party after all.” Our protagonist, high school girl Chiyusaki Sayuki, was laughed at and kicked out of her party. Apparently, Sayuki’s initial skill 〈Potion Create〉 was a dud. Of all places to be ostracized, it happened in the dungeon’s danger zone — and Sayuki was left behind. She sprinted for her life with everything she had, barely managing to escape the dungeon by the skin of her teeth. Sayuki had been through a terrible ordeal, but she wasn’t discouraged. Before long, she wandered right back into the dungeon. “Guess I’ll go earn some pocket money in the dungeon.” She was also hoping she might make some friends, if possible. And so began the dungeon commuting of Sayuki, a loner. But inside the dungeon, she would hear something she never expected. “The skill 〈Potion Create〉 is actually a winning skill, you know?” Sayuki decided to take that claim to heart. As she kept making potion after potion, her level started climbing higher and higher, and—— Despite having supposedly drawn a dud skill, Sayuki began living a fulfilling dungeon life.