Outo Reiyaku Monogatari

The elixir, a magical drug that instantly heals any wound. What if this elixir of legends and fairy tales were real? Dasha, a female knight who has retired for some reason, and Moimir, a charming pharmacist. After a chance encounter, the two hit it off for the elixir and plunge into the stormy seas of adventure. A retired knight and an active pharmacist are on a quest for the wonder drug! An authentic and royal fantasy adventure tale!

(Source: BookLive, translated)