The Extra's Odyssey - Chapter 6 Present Circumstances

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

The planet was invaded by the Tates, and suffered from the devastation of the last ages. In the crisis of survival, some humans awakened powers, and they realised that those mutant beasts could cooperate with their own consciousness and increase their fighting power to two times more.

This kind of animal was called Warpet. Shu Xiaohui was somewhat different from others. When the Tates invaded, he became a hamster and silently felt the presense of another powerful person.

Chen Chengduo watched his companions slowly find their warpet, and wondered where his one was until one day he saw Shu Xiaohui with his mouth full of melon seeds in the corner of the wall…

Others were warpet, his was only just a pet right…

Hamster: You… You don’t look at my small size. I have lucky BUFF!

- Description from Novelupdates

Qin Chen was transmigrated to the Taiyi Holy Land where he became a servant in charge of sweeping the floor. However, on his 16th birthday, he was rewarded with a system where he was rewarded whenever he signed in at a new place.

When he signed in at the Empire Ruin, he was rewarded with the strongest Chaotic Holy Body and the Chaos Emperor Scripture.

When he signed in at the Demon Sealing Land, he was rewarded with the Probationary Royal Armies.

When he signed in at the Alchemy Palace, he was rewarded with the Divine-grade Alchemy.

When he signed in at the Herb Garden, he was rewarded with an Immortality Elixir.

When he signed in at the Empire Palace, he was rewarded with the Emperor-grade Divine Art, Revival.

…

Qin Chen thought he could just spend the rest of his life signing in at different places until he became invincible.

However, when the ruin of the Great Kingdom appeared inside the holy land, people from other holy lands, prestigious families, and even ancient empires gathered to defeat the All-Powerful Demon King who appeared with the ruin. The Demon King had killed countless people and had planned to destroy the Taiyi Holy Land.

Qin Chen was left with no choice but to step up. When he killed the Demon King with a single slap, he sighed, “Why do you guys have to force a mere servant to act?”

“Reincarnated into the World of Magic as a demon, the last thing Davis expected was to grow up right amidst the arms of angels. Ever since the group of philanthropic angels took pity on his miserable birth and adopted him, Davis has been forced to keep his evil identity a secret while he signed in to the system.

“”Ding! The Host has signed in at Angel’s Pond, ‘The Saint’s Halo’ is rewarded!””

“”Ding! Devil’s blood activated. Sign in error. ‘The Devil’s Curse’ is additionally rewarded!””

“”Ding! The Host has signed in at God’s Throne, ‘Gold’s Holy Axe’ is rewarded!””

“”Ding! Devil’s blood activated. Sign in error. ‘The Devil’s Manifistation’ is additionally rewarded!””

After a thousand years of quietly signing into places in the City of Angels and being rewarded with double the rewards, Davis’s true identity finally came to light! Now as a true Devil, Davis had both the world of angels and demons surrendering at his feet!”