The Genius Prince's Guide to Raising a Nation Out of Debt(2019)

Souda, Baikoku shiyou: Tensai Ouji no Akaji Kokka Saisei Jutsu

Wein, a young prince, is in charge of the politics in a weak country with no resources, human resources, or troops. Together with a young girl named Ninym, who serves as his aide, Wayne shows his brilliant skills as a politician with a secret wish. "Sell the country and get out of here"! Yes, Wayne's wish was to live a comfortable life in retirement! However, his plan took an unexpected turn when his subjects become to favor him making it difficult to fulfill that wish. The tale of running a weak government and full of unexpected surprises, begins here!

(Source: Manga UP!)