Stand-in Bride

She grew up with her father missing, and her mother remarried. Living with her grandmother in the countryside, she skipped classes, got into fights, and got drunk, marking her a troublemaker and ruffian in the eyes of others.
At nineteen, her mother took her back to her stepfather's house.
"Harper, it's your luck that you are marrying Mr. Brooks on behalf of your sister. You should seize this opportunity."
She was considered worthless in her mother's eyes, a sacrificial lamb for personal gain.
Everyone knew that Mr. Brooks had a debilitating illness, causing a complete change in his temperament and appearance, with only two years left to live.
Since she married Mr. Brooks, his illness miraculously disappeared. However, when someone investigated a case from a few years ago, they unintentionally revealed Mrs. Brooks's true identity...
Everyone was shocked beyond belief.
She was a hidden boss.