As of my knowledge cutoff in September 2021, Luffy, the main protagonist of the One Piece series, does not possess or regularly use a sword as part of his fighting style. Luffy's primary abilities revolve around his rubber-based powers as a result of eating the Gum-Gum Fruit, allowing him to stretch, deform, and manipulate his body.

While there have been instances where Luffy temporarily wields a sword, such as the Gum-Gum Scythe during the Dressrosa arc, it is not a consistent or defining aspect of his character or combat style. Luffy primarily relies on his physical strength, agility, and the unique abilities granted by his Devil Fruit to engage in battle.

It's worth noting that Luffy's fighting style emphasizes hand-to-hand combat and creative use of his rubber abilities, making swords unnecessary for his preferred methods of combat.