Olivia, a renowned and highly skilled “Black Apothecary,” is tormented by memories of her previous life as a former saint who was executed. Determined to live peacefully in this life, she spends her days quietly in a remote forest as a simple herbalist. One day, a beautiful knight appears and requests her cooperation with the knight order. Wanting to avoid trouble, Olivia refuses—but due to an unexpected turn of events, she ends up accompanying him anyway…!? A tale of a reincarnated ex-saint seeking peace, fate dragging her back into the spotlight, and the bond that begins to form with the knight who seeks her help.