Her Fool Was the Hidden King

Gwendolyn spent three brutal years protecting a brainless fool, mistaking him for her dead fiancé Alden. She had no idea he was actually his twin brother who used forbidden magic to save the Aethelgard and became mindless, Alaric, the world's supreme sovereign. Now cured, Alaric hides his sanity to silently ruin everyone who abused her. But when her family forces her to marry, the disguise shatters. He asks: Will you marry me, not as his widow, but as my queen?