In Duke’s Eldest Son is a Regressed Hero, Aiden Albireo, once a legendary hero known as the “Dragon Slayer King,” is betrayed by those he trusted and left for dead. However, he is unexpectedly reincarnated in the body of Aiden Remez, the eldest son of a duke with a poor reputation. This new life begins 15 years before the resurrection of the Monarch of the Underworld, a being Aiden once defeated. Now, he must navigate his new identity while grappling with the fact that the very Underlord he had slain resides within his soul.
The story revolves around Aiden’s struggle to reconcile his past as a hero with his new life as a nobleman, all while preparing for the upcoming resurrection of the Underlord. Themes of betrayal, revenge, and redemption are central to the plot, as Aiden aims to avoid repeating the mistakes of his past life
