Naruto System in One Piece - Chapter 42: Leiyin vs. Diamante

With the Goddess’ blessing, he became a 『Divine Knight』 and founded an Empire.
As time passed, he grows older, and by the time the heavens called for him to come, the Goddess showed before him, asking for his last wish.

He wished to be reincarnated in the future.
He dedicated all his life for his people, he had no time to master his own arts.
This time, he wishes to live for himself, forging his body to the utmost limit.

The Goddess complied with his wish.
In the far future, the King shall reincarnate as the 『daughter』 of a renowned Knight family.
And, under some circumstances, she is labeled as a failure of a Knight, however——

「How convenient. I can stand on the foremost line without needing any rank. No better training than actual combat!」

Thus, the legend of the world’s strongest, most beautiful Knight Disciple (♀) has begun—

The tender girl, Li Qiao, transmigrated into a delicate bride in a poor family.A rural household registration, between two decrepit houses.What she didn't know was that the unambitious loser of a husband would one day become a commercial tycoon, possessing the highest status and countless wealth.She was even less aware that her reborn stepsister was determined to replace her and become the wealthy lady of the house.The stepsister often urged her to leave, “Brother-in-law drinks and fights, he's irresponsible and doesn't deserve you.”Li Qiao was irritated on a daily basis, “He says he can annoy me to death.”The stepsister added, “He's too poor, you and the child will follow him to a life of hardship.”Li Qiao's face blushed with shyness, “He says one child is not enough to split up over, unless we have another one.”The stepsister: ……

Bai Yixi accidentally slipped into a book and lived in heaven and earth as a child.

What? ! The sickly little boy who treated her as an enemy when she was little is the hero!

What? ! The boy she bullied and cried when she was a child is the male partner!

What? ! The girl who was deceived from candy when she was a child is the heroine!

Also, she turned out to be a cannon fodder female supporting role. For a moment, Bai Yixi was confused in the wind, and then Yixi ran away decisively.

Three years later, she returned to high school.

Wait, male protagonist, weren’t you from the Eleventh Middle School next door? ?

Wait, male supporting actor, aren’t you gentle with the heroine? ?

Wait, hostess, why are you so jealous of my gaze? ?

Male protagonist: “Is it difficult to love me?”

Male supporting actor: “Without you, what use would I have for this championship?”

A certain Yixi: “Where is my original male lead and supporting actor?!”

Yixi wanted to escape again, but was trapped by a certain boss. The boss’s eyes were dark red and there was a cold smile on his handsome face: “If you run away again, I will die in front of you.”

Bai Yixi shouted: This is not the male protagonist I know. The male protagonist in the novel does not have paranoid and morbid attributes!

Seeing the increasingly darkening male protagonist, Bai Yixi gave in decisively: “Come on, kiss me, don’t be angry!”

ps: 1. The male protagonist has a split personality.

2. It is an extraordinary world with supernatural and fantasy elements.

- Description from novelbuddy

Yu Linglong is the shu (born of a concubine) daughter in a general’s family. Since her mother was only a tribute dancer, her position is the lowest of the low. She used to live with her mother outside the father’s residence, and they only received some monthly money from him. He didn’t bother seeing them. But when her mother dies, she moves into the general’s residence.

The general is a very irresponsible and violent man. He doesn’t really get attached to women, just letting his lust dictate his actions. His wife is a jealous woman, who killed one of his previous concubines, because he doted on her too much. She similarly wants to get rid of Yu Linglong, in part to vent her frustrations over her husband’s cheating habits.

Because the sixth miss – the general’s legitimate daughter, was bitten by a snake, she needs detoxification. The cure was apparently getting poisoned by scorpions, to fight one poison with another. But since she’s already weak, they decided it would be better if she drank the blood of someone poisoned by scorpions instead. The general’s madam naturally decided to use Yu Linglong’s blood. During the process of getting bitten by the scorpion, the original timid Yu Linglong died of fright (and maybe poison? it’s never made clear). Then Yu Mei takes over her body.

Yu Mei is a modern woman. She was some mafia boss, so she’s very capable with fighting and overbearing attitude. She died because the man she fell in love with betrayed her and killed her. So she doesn’t trust easily afterward.

Since she took over Yu Linglong’s body, she refuses to adapt to the circumstances of a lowly illegitimate daughter, and uses her violence to fight for a peaceful life, where no one will challenge her and plot against her. Basically, she beats them up into submission. In the meantime, she acquires a tail – a very persistent prince, who only seems to stick to her harder, the colder she treats him. Did ancient men have such heavy tastes, she wonders.

- Description from Novelupdates