Sword Sovereign of the Celestial Emperor - Chapter 223, In Advance

Reiji Saeki, who lives in the north eastern countryside town, lost his life in an accident during summer vacation. ……But before he knew it, a mysterious ball of light hovered in front of his eyes in a world of whiteness. That ball of light was a magician from a parallel world, and is looking for a person qualified to inherit the magic they had created to prevent it from being lost. Reiji, who rode on that suggestion, now lives in the parallel world Elgin, with a new body and powerful magical power.

Humanity was living peacefully on Earth for millions and millions of years until the day unknown monsters from beyond space invaded them.

When humans were about to disappear, some people with abilities came out to the light and shared their knowledge and powers with the world, and together, they managed to push back the invaders during a terrible war that had lasted for years.

This war had created many orphans, and among them, Kye had lost everything, even his parents. And the only thing he received from their death was a pale-looking necklace.

However, once the necklace finally activated, a system was given to him, and his life changed completely.

The system gave him quests to do, and Kye complied. He was getting stronger every time he achieved them, until the day it gave him a weird quest.

[You have one day to kill the one who had sinned. If you do not kill, you will die.]

Shi Qing Xia is practically an angel.

Kind, sweet-hearted, and good at her studies, she was admitted to the top university in Taipei.

However, the living expenses for the metropolitan city were far greater than she had ever imagined, so she started to work as a private tutor for wealthy families to make ends meet.

On her first day of work, she met Zhao Yi Bo and Zhao Yi Xuan, a pair of neglected 16-year-old genius twins whose prosperous and wealthy parents heartlessly abandoned in Taiwan. Shi Qing Xia found them to be gentle, compassionate, friendly, clever, mysterious, pitiful and attractive.

But appearances can be very deceiving…

Because behind those sweet smiles…

Deeply twisted and cruel demons lurked, waiting to rip apart the wings of this angel, condemning her to an eternity of conflicted bittersweet suffering — a rollercoaster ride of a heart-wrenching, twisted, and tragic romance more extreme than what someone so innocent could possibly imagine.

- Description from Novelupdates

In a parallel world filled with pet beasts, people tame, train, evolve, and trade beasts.