HP: The Arcane Thief - Chapter 22: Flying and Undercurrents

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Julian, the son of Duke Alden and the grandson of Grand Duke Augustus stood Infront of the crystalline ball that emanated mana.The crystal absorbed his mana and started glowing with purplish hue, with a sparks of lightning.“Yes, I have unlocked Lightning Affinity,” Julian said, a spark of excitement lighting up his blue eyes.Suddenly, the ball began absorbing too much mana, Julian's eyes widened in horror as the energy swirled out of control, crackling with an intensity that was and terrifying. Just as he realized the danger, the ball erupted in a blinding flash, a shockwave of power surging outward.Julian wasn't hurt, but he felt a strange sensation as a dark mist swirled in front of him. Suddenly, he saw a strange entity, a shadowy figure, slip into his forehead.Then, Julian heard an unfamiliar sound echo in his head:“WELCOME TO THE MILF SYSTEM.”Connecting....SuccessInitializing.......Success“FUCK THE MILFS AND GET STRONGER, CONQUER THE MILFS, CONQUER THE WORLD.” , The voice saidCuriosity piqued, Julian quickly asked, “Can you tell me more about the MILF SYSTEM?”The voice continued, ”Sure, The MILF SYSTEM will help you reach unimaginable power as a mage. You will need to complete the tasks assigned to you and earn points.“

Razé was a cheat soldier at the age of 15, thanks to the memories of her previous life. One day, she was summoned by her superior – the devil Prime Minister and was ordered to go on a long-term solo mission. She was expecting a harsh mission, but…

“I knew you are the right person for this, Lieutenant Colonel Razé Orphan. I want you to attend the Centrior Imperial Magic Academy starting from this spring.”

“…..what?”

Well, it seems that she has been appointed as the “bodyguard” for the prince and other noble’s kids. And so, she was enrolled to the school where the aristocratic-sama gathered.

Although she was puzzled by the glittering school life, she was trying to live a life so as not to be bullied in the future. But it seems there was a secret that she didn’t know hidden in this world.

“Hey!!!!!! No one told me that this is an otome game!!!!!”

As a bodyguard, her life would be over if any of the noble kids got hurt. But then a young lady who claimed to be the ill-fated villainess came by. If the girl died, won’t she be dead too?

Today, Razé will continue to watch over her school life (with her own life on the line).