Jakushou Kokka no Eiyuu Ouji: Saikyou no Majutsushi dakedo, Sassato Kuni Dete Jiyuu ni Ikiteee!

Despite being a small nation, the Kingdom of Ulmira continues to win wars against the surrounding great powers. The driving force behind these victories is the second prince, Allen, who has mastered magic and possesses overwhelming combat skills. The man who has come to be called a "hero" is actually—"I want to get out of this country! I want to have fun with girls!" This is the story of the strongest prince who wants to live a dissolute life and leaves his mark on history.

(Source: Overlap, translated)

*Note: Chapter count includes eight bonus chapters.*