Demon Hunter (Teramachi Akeho) - Chapter 45

He died on the wedding of the girl he had a crush on, after a long and successful career. After convincing Yama to send him back to the world, he decides to fix the areas in which his life went wrong. Realizing the lack of love and romance in his past life, he sets out to conquer the hearts of various women.

From a media tycoon’s daughter to a poor plumber’s girl, but it seems that Yu Yao is unfazed? She opened the eyes of the sky, and her life has been opened all the way. She is an eighteen-year-old girl, but as soon as she turns around, she becomes a big boss who no one in the entertainment industry dares to offend.

- Description from Novelupdates

The protagonist transmigrates into a novel and gains a system where they grow stronger by simply writing in a diary.July 7th, sunny: “The boss’s outfit is hideous again. Wouldn’t it be better to wear something cooler?”July 7th, evening: “I’m about to have my engagement called off. So excited! How should I act?”July 7th, evening: “Lin Qingyue, the female lead, is probably going to drown her sorrows in alcohol.”The protagonist thought it would be easy—just jot down daily musings, record life’s events, and earn rewards. All while playing the part of a villainous, bootlicking second-generation rich kid, moving along with the original plot.But unexpectedly, the female leads gain access to copies of the diary entries.One by one, they stop following the script, and the plot spirals completely out of control.July 10th: “The female boss is an idiot—no one would want her.”Soon after, the protagonist gets punished at work, all because they entered the office with their left foot first.