Reincarnated as the Demon King's Son - Chapter 691 First Order

The unruly madame is playing as if she was a Russian matryoshka! Do you think that under the the vest is her real identity? Apologies, but there is still a vest under that vest. And then a couple more vests under that!

Madame! Just how many identities do you have !?

- Description from Novelupdates

She was a medical genius from the Noah Medical Academy as well as a drug producing specialist. After sleeping for three days, she had returned to the ancient era and become the loyal marquis palace’s ignorant and silly young miss.

Fein Rizal was an aspiring doctor who was accidentally transported to a world dominated by Supernatural Beings and people with unusual abilities. Because of the unfortunate circumstances of the body's original owner, he was caught up in a mysterious incident in which his group of friends committed suicide. As the sole survivor, he was now being pursued by the perpetrator, who wished to silence him. Fortunately, he has the ability to level up his talent in everything, which may be the only way for him to survive in this insane world.