Naruto System in One Piece - Chapter 16

Transmigrating into the novel, [The Emperor of Luck] Gu Xia received the despair villain system and became a small villain who is destined to be face slapped by the protagonist then eventually killed.

Having been through the plot thousands of times and being failed by the system every time, he finally snapped.

“System! What did I do wrong this time!?”

[Host, please calm down... There has been an error in the world that I have no control over. As an apology I can grant you extra rewards once you complete the plot!]

Gritting his teeth and having bloodshot red eyes Gu Xia finally had enough.

[I quit being the villain! Fuck the plot, fuck the heroine's, fuck the protagonist, fuck everyone, I just want to live my life without being face slapped! I QUIT!]

Unknowing to him all of the heroines could now hear his inner voice…

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

Five hundred years later, a superhuman talent cultivated by the state perished during a mission, and his soul transmigrated, taking possession of the body of a young master from a prominent family who suffered from an anxiety disorder. From that moment on, his extraordinary life began, spanning across various fields such as business and medicine. Wherever he set foot, others could only look up to him.

Jian Chen, the publicly recognized number one expert of the Jianghu. His skill with the sword went beyond perfection and was undefeatable in battle, After a battle with the exceptional expert Dugu Qiubai who had gone missing over a hundred years ago, Jian Chen succumbed to his injuries and died.