Let's Buy the Land and Cultivate It in a Different World (Manga) Vol. 8

SELF HELP OR SELFISH? Kidan possesses a gift called the Supreme Wielder and was summoned to another world. Together with the mermaid Plattie and the dragon Veel, he has built a homestead on the frontier. His farm grows ever larger. Elves, demons, witches, and humans are all welcome. Then one day, Plattie's older brother, Prince Arowana, pays a visit to the farm to say goodbye. He is departing on a journey for self-improvement! What will his sweetheart Puffer do...?!