Lord of Ascension: The Birth of Chaos - Chapter 63 The Figure with Dark Magic

The gods visit my shop. I travel across countless worlds with them. But then… “This is my sword, the Heavenly Tyrant Blade.” “This is the Ruyi Jingu Bang.” “This is the lightning spear I once wielded.” Their payments are… peculiar.

Yeon-woo had a twin brother who disappeared five years ago. One day, a pocket watch left by his brother returned to his possession. Inside, he found a hidden diary in which was recorded “By the time you hear this, I guess I will be already dead….”

Obelisk, the Tower of the Sun God, a world where several universes and dimensions intersect. In this world, his brother had fallen victim to betrayal while climbing up the tower. After learning the truth, Yeon-woo decided to climb the tower along with his brother’s diary.

“From now on, I am Jeong-woo Cha.”

Those people killed her grandmother, murdered her younger brother, trampled the people she deeply cared about, and even took her own life.

It was because she trusted her ambitious stepmother and half-sister;

because she mistakenly believed that womanly virtue is to have no talent;

because of her noble status and origin….This is what caused her death.

Buried in river water, Ouyang Nuan, gritted her teeth and spoke, “I, Ouyang Nuan was wronged in death. Even if it takes forever, I will become a devil, and in the next life, will not let you off!”

When she once again opened her eyes, Ouyang Nuan was sent back in time to when she was twelve years old. Around this age, her forehead was scarred, her brother fell into the water, and in three years she will be married…

In this life, she will try to change everything to guard and protect those she cares for from those with treacherous intentions. She will live a glorious life!

- Description from Novelupdates

Having lived a normal life all his life and died without being able to fulfill his desire and when he’s given a task by a god, watch how he takes the protagonists girls while making it hard for the hero.