One Piece: From the Start, I Lay Low Until I Become Emperor, More Children, More Blessings

[One Piece + Levelheaded Protagonist + Multiple Heroines + Martial Arts + Swordsmanship + Devil Fruit Development]

Transmigrated into the world of One Piece at age five, with twenty years to go before Luffy sets sail...

He keeps a low profile and builds his strength early on, then creates a force of his own later.

A levelheaded protagonist who focuses on martial arts, swordsmanship, and developing his Devil Fruit powers.