Shortly after the events in Steel and Flame, Zeneth and Ruwa are visited by a very unusual guest.The kobold Natron hires them to protect her during a grand tour around Avlaan, forcing the two officers to take a few detours before taking a bigger mission requested by Sitri, the great Azoth Apothecary.Eventually their very same duty to the small fae brings them back on the path to meeting the famed alchemist, who will entrust them with a task of epic proportions on board of his skyship, the Queen of Hearts.Once again the two Auxiliarii officers embark on a quest beyond their expectations.Always loyal, no matter the challenge. May they succeed in all their endeavors.Reagent and Toxicant follows the cliffhanger left in Steel and Flame, continuing the epic adventure of the adorable wyfwolf Ruwa the Red and her beloved half demon Zeneth of Antua.