At Sea: I'm One of the Five Emperors, and Luffy's Big Sister!

● The protagonist on the cover is a man who becomes a woman. There are two transmigrations, no System, and plenty of laughs!

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● A modern high school student is reborn in a world of swords and magic as the eldest daughter of an imperial marquis's family.

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● After successfully defeating the Demon King alongside the hero, she is transformed into a demon by the curse the dying Demon King places on her. She is also sent to the world of One Piece, to the year before Roger's death. Garp adopts her, and she begins an ordinary life in Windmill Village.

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● Twelve years later. The girl had been content to stay home and study "immortality magic," but unexpectedly became "the most vicious and brutal criminal in eight hundred years"... and was nominated as one of the Five Emperors by Morgans!

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● A year later, after completing the test set by an "old friend," the girl returns to the world of pirates, only to run into Luffy, who's preparing to take down Arlong.

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● The girl can't help but ask the question on everyone's mind:

"Luffy! Pillaging, killing, and looting are what pirates are supposed to do. Do I really have to teach you that, little brother?"

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◎◎ Great story, plenty of foreshadowing. Join the discussion in the comments! ◎◎

This novel and its characters are entirely fictional. Any resemblance is purely coincidental. Do not imitate.