Naruto System in One Piece - Chapter 427

Xia Lian, a 21st century military doctor died in an explosion and found herself transmigrated to the body a 12 year girl. Her mother died and her father abandoned her and her little brother for another woman.

He—an enigmatic and cold-blooded soldier with a mysterious background.
She—a ruthless and bloodthirsty spy.

Wu Lai was an ordinary high school student. One day he was struck by a flash of lightning from a different world, and suddenly entered a fantastic world full of magic and swords. Since then, he started a totally new life. In this supernatural world, he had his ups and downs, experienced numerous battles, subdued powerful evil beasts, and fell in love with a belle. His nickname “Demon King” was remembered throughout the ages there.

Stay or return was a question. In the face of this choice, Wu Lai, with the nostalgia and gratefulness for the original world, finally chose to stay…

Here was the legend of “Demon King”…

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