Toaru Majutsu no Index: New Testament - Volume 17, Epilogue: Or Doubt Contains the Truth - Bet_Time.Red_or_Black.

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.

- Description from Novelupdates

She had never expected that she would slept with her deadly enemy,but it turned out to be a good match for both of them.

while after marriage ,his indifference finally angered her.

You damn bastard!

She is one of the best thieves that the world has seen in the 24th century. However, not even in her wildest dreams had she imagine that she’d be reincarnated as a good-for-nothing orphaned Seventh Miss of the Vermilion Bird Family. She finds herself stuck in a family that mistreats her, as well as an unfamiliar place with no support system.

Ever since Su Tian had transmigrated, she received a “Villainous Bosses Mentoring System” that could automatically identify villainous bosses IN THE MAKING.

As for her missions, they were a little more complicated. For example:

Stopping the boy in her class from deviating onto the path of becoming a villain;

Turn the boy who was going to create a global financial crisis into Jack Ma of the new world;

Talk the strange girl working at the toy shop out of her spending habit, because she will be the cause of hyperinflation!

And the boy from the countryside that she ran into, please give up on developing bioweapons! Why don’t you focus on the Nobel Prize instead?

Just when Su Tian thought all the little villains were growing straight up into upstanding people under her “education of love”, the small villains brought about a big villain…

The young man has slender arms and legs and he cornered her into the restroom. He looked deeply into her eyes said, “I also need …”

Su Tian shuddered, “What… what do you need?”

“The education of love,” said the young man meaningfully!

Ten minute later, Su Tian… was educated.

System: This system is only responsible for identifying villains IN THE WORK. Matured villain are outside of its parameters.

- Description from Novelupdates