Supreme Casanova: Ultimate Harem System - Chapter 31: Going To Class.

I just lost myself in the deep and shallow temptation of her.
——by Jiang Hanyu
Everyone knows that the person Nan Gao doesn’t mess with is Jiang Hanyu
She is arrogant and fierce, relying on beauty, a proper little overlord in school
Everyone thinks that the best relationship with Jiang Hanyu is to call him brothers.
But one day, someone found that Jiang Hanyu was holding the hand of the goddess of coldness in the class and lowered his eyebrows after class.
Unruly girls become gentle and charming
He also said in an unbearable and irresistible voice, “Si Nian, will you give me a kiss?”
Then everyone knew that the best relationship with Jiang Hanyu was…

TIPS:
1. The Great Demon King X Miss Gao Leng
2. Campus text

- Description from novelbuddy

The once revered Alchemy Emperor returns to his fifteenth year. In this lifetime, he not only seeks to rectify all past regrets but also aims to achieve the pinnacle of martial arts!Compared to cultivation techniques? My lackeys have divine-level technique in hands.Compared to elixirs? My top-tier elixirs are fit only for feeding dogs.Talents? Any genius who encounters me will find their fate crushed!Prosper under my lead, oppose me and meet your demise!

In a world fractured by conflict and haunted by shadows of the past, Kokushibo—the first Upper Moon demon—meets his end, only to awaken in a new life. Reincarnated as Crimson, a child born into a different family, he carries the memories of a past he cannot escape. Burdened by centuries of guilt yet indifferent to the present, he resigns himself to duty—until an unexpected bond with his newfound family begins to thaw his hardened heart. As he struggles between the weight of his past and the weight of the new life, Crimson must decide whether he will remain shackled to his former sins or embrace the possibility of peace.

To be exact, the female lead is an “older sister” type, amid many beauties and handsome guys, she's no white lotus.Also, it's said that the name of this book is the same as a brand of sheep's milk powder.