He transmigrates into the world of One Piece and obtains the Second-Dimensional Swordsmanship System. From the start, he gains the abilities of the new Third Espada, Tia Harribel.
He can acquire all the sword techniques and abilities of people like Yamamoto Genryusai Shigekuni...
Kaido: "I knew I was right about you back then. You're a damn fine vice-captain."
King: "Excellent swordsmanship, powerful strength, and an extremely clever mind. You're the vice-captain through and through."
Sengoku: "What a huge pain. That brat is such a headache."
Iblis: "To become the World's Strongest."
This novel and its characters are entirely fictional. Any resemblance is purely coincidental. Do not imitate.
Is the protagonist female? Not fighting the war?