Global Reincarnation: Only I Know the Plot - Chapter 15:

Civilization is destroyed and records lost. Only Dudian survives in a cryogenic sleep. Three hundred years later, Dudian wakes up and must become Dean to survive. Who can he trust in this world overrun by monsters without and within?

Life is unpredictable. Her husband loved her stepsister, deposed her as Empress and even forced her son to death. In that Cold Palace, she was forced to drink poisonous wine. So in the next lifetime, she made a promise to never do good deeds and help others, to never step into the palace and to never become the Empress!

Kōdo Ikusei Senior High School, a leading prestigious school with state-of-the-art facilities where nearly 100% of students go on to university or find employment. The students there have the freedom to wear any hairstyle and bring any personal effects they desire. Kōdo Ikusei is a paradise-like school, but the truth is that only the most superior of students receive favorable treatment.The protagonist Kiyotaka Ayanokōji is a student of D-class, which is where the school dumps its “inferior” students in order to ridicule them. For a certain reason, Kiyotaka was careless on his entrance examination, and was put in D-class. After meeting Suzune Horikita and Kikyō Kushida, two other students in his class, Kiyotaka’s situation begins to change.Note:- Even though Volume 0 is the prequel of this series, it is advised to read till Year 2 Volume 8 beforehand to avoid getting spoiled (which is precisely the reason why it was released after Y2 V8).Anime:-Season 1: Volume 1 to 3 + Volume 4.5Season 2: Volume 4 to 7 + Volume 7.5Season 3: Volume 8 to 11 + Volume 11.5

She was born into a powerful family of the nobility, a blue-blooded aristocrat as capable as any man. He rose from humble origins up the military ranks, an iron-blooded knight with high ambitions. A transaction for power severed her from her childhood sweetheart. A tardy encounter was the beginning of his and her vow to meet life and death under heaven, standing shoulder to shoulder.

Political intrigue, dynastic succession struggles. He trampled through it all in the toil of becoming emperor.

Old enmities became new disputes, concerning life and death of entire families. She entered once more into the palace, changing the entire political climate of their world.

Meeting once again, they had become strangers. The peach blossom were all fallen, no more than a golden age grown cold.

- Description from Novelupdates