Aden Albireo, the "Dragon Slayer King", was a hero who saved the world by eliminating the Berserker and the Underlord. However, he was betrayed by those who whispered friendship to him, and met his death...
"I didn't know I would be resurrected like this?!"
15 years before the Underlord's resurrection, 'Aden Albireo' reincarnated into the body of the eldest son of a unheard-of duke's family, 'Aden Remes'! And...
"It's been a while, Dragon Slayer King!"
"The Underlord I thought I had defeated is inside my soul?!"
Will Aden be able to end his uncomfortable cohabitation(?) with the Underlord and prevent his resurrection?

Read the comic The Hero Became the Duke's Eldest Son online, along with others like The Beginning After the End, Solo Leveling, Omniscient Reader's Viewpoint, Jujutsu Kaisen, The Greatest Estate Developer, Revenge of the Baskerville Bloodhound, The Swordmaster's Son, After Ten Millennia in Hell, I’m the Max-Level Newbie, My Blasted Reincarnated Life

Action

Adaptation

Fantasy