"Drug Store in Another World - The Slow Life of a Cheat Pharmacist" centers on Reiji Kirio, a modern-day pharmacist who is transported to a fantasy world after falling asleep at work. In this new realm, he discovers he possesses a unique ability to create highly effective medicines and potions using his knowledge of pharmacology. Reiji opens a small pharmacy in a rural village, where he begins to treat the ailments of both humans and mythical creatures. His reputation as a skilled pharmacist quickly spreads, attracting a diverse clientele, including adventurers, demons, and spirits.

Reiji’s life becomes intertwined with several key characters, including Noela, a wolf-girl who becomes his loyal assistant and protector, and Mina, a ghostly spirit who assists in running the pharmacy. The narrative unfolds in a slice-of-life format, focusing on Reiji’s daily interactions with customers and the challenges he faces in creating remedies for unusual and fantastical ailments. The story emphasizes his resourcefulness and ingenuity as he adapts his modern pharmaceutical knowledge to the magical and often unpredictable world he now inhabits.

The series balances lighthearted moments with occasional emotional depth, exploring themes of healing, community, and the impact of kindness. Reiji’s relationships with Noela and Mina evolve naturally, adding warmth and humor to the narrative. While the overarching plot is episodic, it occasionally delves into larger mysteries of the world, such as the origins of Reiji’s abilities and the broader implications of his presence in this alternate reality. The tone remains consistently relaxed, reflecting the "slow life" premise, with a focus on the quiet satisfaction of helping others through his craft.