One Piece: Unreal Adventure - Chapter 19: Improvement

The first time Yan Zhaoge crossed worlds, he landed in a martial warrior civilization that was at the peak of prosperity. He ended up in the book storage building of the the Divine Palace, which collected and preserved the classics of the entire world from all fields of knowledge. However, a world class calamity struck soon after and even the Divine Palace was destroyed.

Yan Zhaoge’s soul once again crossed over, but this time he arrived in the same world, except countless years have passed.

With his brain full of rare books and classics from the era of peak prosperity, Yan Zhaoge’s second crossing over to the present era was like a gamer who was used to playing hell mode suddenly finding himself playing the game on easy.

That was just way too awesome.

But before that, he needs to fix a certain problem.

“I’m not a main character? In fact, I’m actually the main character’s love rival and the antagonistic Mr. Perfect senior martial brother? This script is wrong!”

- Description from novelupdates

“What I want, the Heavens shall not lack! ”

She is the underworld Ghost Doctor’s only disciple, who accidentally transmigrated into the body of the main wife’s daughter in the general’s mansion. She used to be a punching bag.Now, she stepped on her dregs of an older sister, put her father’s concubine in her place, and teaches any objectionable aristocratic ladies a lesson.

Her days are rather free and unfettered. But when did that cold as ice prince from the rumors, sporting a deadpan face all day long, fix his gaze on her?
He unexpectedly fawned and pandered to her like a devoted dog?

“Go away, you rotten man! Careful or I’ll needle you like a pin cushion!”

“Wife, why are you so fierce? As a husband, I’m so scared”
….the man is all smiles as he approached, his eyes gleaming with a cunning light.

- Description from Novelupdates

Hiding in the Cold Palace and eventually becoming a Boss of Sorts. Li Mu was transported to a fantastical world and became a measly eunuch of the State of Xia. Despite having initially thought that his life would be a miserable one, he had unexpectedly acquired a check-in system.