The Alchemist Who Survived Now Dreams of a Quiet City Life II, Vol. 3 (manga) — Usata Nonohara

The Aguinas family dominated the alchemical market for centuries, until Mariella awoke. No other living alchemist possesses a leyline pact like hers, allowing for the creation of potions after the stampede— something the head of the Aguinas family has now discovered. With Mariella’s quiet life of potion-making standing between an aristocratic family and the monopoly they once held, how much longer can the peaceful life she's built remain that way...?