The Icewolf Chancellor's Cast Away Conjuror and the Flames of his Devotion

The hardworking daughter of a marquess, once overlooked, learns her true value through love.
Sophia, the diligent daughter of a marquess, is engaged to the second prince, Delm. Both serve at the Royal Magic Research Institute, but as his fiancee, Sophia is forced to shoulder his work.

When she invents a new form of magic, Delm steals her research and registers it under his own name. When she demands it back, he refuses and even accuses her of lying.

Hailed as a genius, Delm basks in glory while Sophia is cast away. Stripped of her reputation, her laboratory, and her engagement, she returns home in despair.

Then fate takes an unexpected turn as Sophia becomes engaged to Leo Santorina, the prime minister feared as the "Icewolf Chancellor." Yet behind his cold title lies a kind, gentle man. Cherished and supported by him, Sophia begins to bloom, proving her brilliance while the man who betrayed her faces his downfall.

(Source: MangaPlaza)