Tomodachi no Imouto ga Ore ni Dake Uzai - Volume 2, Chapter 4: Only the Club Advisor is Strict with the Sports Club

Witnessing her boyfriend cheating on her with her bestie, Shiyao was so angry that she went to a pub for fun and met a man, who was really a piece of work. After a crazy night she fled away, but was embarrassed to know that the man she slept with was her boss You Ze.
Jesus, give her a break!

- Description from Novelupdates

Qin Guan was reborn and sent back to his final semester in High School 18 years ago. Getting a second chance at life, he works hard to turn things around and eventually become a Prince Charming. What will his life be like the second time around? What will he have to go through? How will he succeed in turning from a loser into a Prince Charming?

Synopsis ___________________ Viretta Medlit is a hopeless braggart. One day, she casually boasts to a young man she meets about her unfortunate arranged marriage, only to discover that he is her fiancé. To make matters worse, her exaggerated claims stir something within him. “Are you prepared to face any hardship?” “Of course. If it's for the one I love, I’d even hunt a dragon!” “Then let’s go hunt a dragon. And break off the engagement afterward.” Thus begins Viretta's journey to hunt a dragon… All in the name of breaking off her engagement with a fiancé she actually finds quite agreeable!

She was a combination of a high iq scholar and a black-bellied prince charming. She was a one-on-one, two-on-one, two-on-one, absolutely refreshing, and she was welcome to jump into the pit.