The Apothecary Diaries is a Japanese light novel series written by Natsu Hyūga and illustrated by Touko Shino. Since 2011, it has been serialized online on the user-generated novel publishing website Shōsetsuka ni Narō. From Wikipedia
Fans are interpreting Natsu Hyuga’s hint of back-to-back announcements as a likely sign of an imminent Season 3 renewal