MTL - Demon King’s Political Marriage - Chapter 4 Pre-marital training (below)

She was a peerless genius in the way of medicine, holding the Medicine King Cauldron in her hand.

Once she transmigrated, she became a lowly little medicine slave in dispensary.

Physicians made her life difficult, princesses humiliated her, even her fiancé came knocking on her door to break off the engagement?

What was that?!

However, she had the cauldron in her hand; the top-notch medicinal herb was in her hands. She stole rare and precious herbs, punished the slanderous, plotted against the petty, treated the Emperor’s sickness, and saved the Crown Prince.

Then, the imperial edict turned the medicine slave to a concubine and received endless doting. It was unbreakable. Wait… didn’t Prince Jun, who wielded great power in the imperial court, say she was a a detestable individual?

As the saying goes, the concubine was good in the way of medicine.

However…

- Description from Novelupdates

Growing up in the slums, deprived of freedom, being enslaved by his parents and thugs, all Lucifer wanted was a life of freedom, a life that he could do whaver he wanted, not being ordered by anyone.And then luck came to Lucifer when he awakened the system, and even luckier was that he was able to raise his Destiny Rank to Unpredictable.But in return...he was turned into Freedom's Most Loyal Slave

Her parents died in planned accident by her uncle. They used her in every way they can. They planned to sue her so she wont take her fathers company back. They want to destroy her life making her penniless. No one knows that she is the not the same girl who was played as puppet in their hands. Five years changed her a lot. Now she is a hidden genius still acting pityfull to take revenge.