Koko wa Ore ni Makasete Saki ni Ike to Itte kara 10 Nen ga Tattara Densetsu ni Natteita - Chapter 257 - Structure Analysis of the Bomb

Jiang Pengji got something called the Court Intrigue Stream System.
System: “Your goal is to become the most prestigious woman in the kingdom (the Queen)!”
Jiang Pengji: “Okay, System. No problem!”
Years later, she met the target by becoming the most prestigious woman (the Empress).
Jiang Pengji: “Well done, no?”

- Description from Novelupdates

I transmigrated into a novel and became the villainess, Serina who comes from the noble Ducal Melford family.

As a well-to-do character, I tried to mind my own business, but the story had other ideas. A self-proclaimed mother brought back a boy – the duke’s heir and a genius wizard – intent on brainwashing and blackening him.

The contents of brainwashing are two things:

1. Obey our family.

2. And fall in love with Serina.

Thanks to that, the brainwashed twisted yandere is obsessed with me…

I can’t do this. I have to undo the twisted character’s brainwashing!

By the way, what’s this situation?

“Now that the brainwashing is gone, I’ll do as I please. So Serina, please, let’s do our best.”

I’ve solved his brainwashing… but why does he seem even crazier than before—

Did I make a mistake?

Based on the popular Vocaloid series, by HoneyWorks, called “Kokuhoku Yokou Renshuu (Confession Rehearsal)“:

Natsuki, a third-year at Sakuragaoka High School, who holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him be her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?

In the current era, people are either normal or are with ‘special abilities’. Cases related to the latter are managed by the “National Anomaly Prevention and Control and Special Species Management Office”.
Qi Zheng Emperor Sheng Lingyuan was reawakened a thousand years later after he jumped off the fiery Red Lake. Xuan Ji, a newly transferred staff to the Reparations Division of the Deviant Control Office, finds himself having to clean up the mess of a revived tyrannical monarch. The two seemed to share something from the past, but unbeknownst to them, a big conspiracy is stirring right underneath their noses that could destroy the balance of the world.

- Description from Novelupdates