What Do You Mean My Cute Disciples Are Yanderes? - Chapter 1038 A Flipped Universe

Amamiya Hiroto is unlucky. His life consisted of misfortune after misfortune, culminating in an unlucky death during an incident on a school boat trip, trying to save a girl he barely knew. After death, he met a god of reincarnation who requested that the hundred or so dead passengers—one of them being the girl he tried in vain to save—be reincarnated into another world.

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

A world where men don’t exist. A kingdom ruled by powerful, dangerous women. And Henry the only male in existence has just landed in the middle of it.To some, he’s a treasure. To others, a possession. But to Lady Seraphina, the most powerful woman in the realm? He’s hers. Whether he likes it or not. Now, trapped in a world of seduction, power, and deadly intrigue, Henry must survive forces far beyond his control before he loses more than just his freedom.