Sei is a workaholic in her 20s. One night, on her way home after finishing up some overtime at the office, she is suddenly enveloped in a beam of light and whisked away to another world. She is summoned there as a saint by a prince, but it turns out she wasn’t the only one! The prince completely ignores Sei and turns all his attention towards the other person he summoned—a high school girl. Sei figures if that’s the case, then she can do whatever she wants! So she leaves the royal palace and finds work at a medicinal herbs research laboratory, where she can pursue her true calling of working with plants. With the help of Johan, the head of the laboratory, and her instructor Jude, Sei learns how to use magic and make potions. However, her saint abilities are brought to light when she realizes that all her potions are five times more effective than they should be. On one occasion, her potion saves the life of Albert, the captain of the Knights, who was on the brink of death. Rumors slowly start spreading, and people begin to suspect that she is a real saint.