In This Life, The Greatest Star In The Universe - Chapter 38:

After 20 years of dedicating his life to opera ever since he had quit the performing arts high school, he had failed at an interview. Losing his motivations, Jo Yunjae depended on alcohol to live out his days until one day, he had been sent back 20 years in time, to the day before his high school admission.

Shu Yu transmigrated and became the original novel’s violent and brutal female Demon that caused the supporting male character, AKA hidden Boss, to become batsh*t crazy. However, right now, the Boss is just a lowly slave that was just given to her. What should she do?

- Description from Novelupdates

This novel is also known as Only I Level Up

10 years ago, after “the Gate” that connected the real world with the monster world opened, some of the ordinary, everyday people received the power to hunt monsters within the Gate. They are known as “Hunters”.

However, not all Hunters are powerful. My name is Sung Jin-Woo, an E-rank Hunter. I’m someone who has to risk his life in the lowliest of catacombs, the “World’s Weakest”.

Having no skills whatsoever to display, I barely earned the required money by fighting in low-leveled catacombs… at least until I found a hidden catacomb with the hardest difficulty within the D-rank catacombs!

In the end, as I was accepting death, I suddenly received a strange power, a quest log that only I could see, a secret to leveling up that only I know about! If I trained in accordance with my quests and hunted monsters, my level would rise.

Changing from the weakest Hunter to the strongest S-rank Hunter!

- Description from Novelupdates

Outer Sect Disciple Chen Yu, assimilates within his body a fiendgod heart.The heart, is the backbone of life, the human body’s fatal vital point. And it can be said that Chen Yu’s heart is actually his strongest defense point, and permits him to overtake demonic beasts, or divine beasts unlimited potential.Henceforth, he steps onto the stage and surges forth on a magnificent scale, in a heart-rending mysterious journey.Talented as a cloud, an unparalleled supreme talent.10,000 races glorious, cross boundary battles.Only my heart, eternal!