Reborn into nobility through heavenly intervention, he was cursed with 【Toxin Decomposition EX】—an ability so unremarkable that family members made him a daily target of ridicule. The turning point arrived when he unlocked the true nature of his skill: by devouring magical stones from vanquished monsters, he could absorb and master their unique abilities. Adding to this revelation, he discovered his shocking birthright—he is the hidden prince of a neighboring realm! The royal palace provided the perfect crucible for his growth, overflowing with powerful magical stones and rigorous training regimens. His dormant potential awakened spectacularly as he progressively acquired stronger abilities, eventually claiming the formidable powers of the legendary Dullahan! A fiercely ambitious fiancée and a lovably inept knight girl join him on his path as the overlooked boy rises to claim his rightful place as "King"!