Banished from the Hero's Party, I Decided to Live a Quiet Life in the Countryside Manga, Vol. 8 — Zappon

Winter has come to Zoltan, bringing a chilly wave to the normally temperate frontier region. Rit's offhanded comment -- “If only we had a medicine that could draw in customers on such a cold day.” -- sets Red about developing a new product, making use of the knowledge he gained from previous adventures. Meanwhile, the Hero Ruti and her ally Tisse have stolen their party's airship and taken flight! But where could they be headed...?