Monkey D. Luffy and a fraternal twin brother beside him. They look exactly alike

Monkey D. Luffy and a fraternal twin brother beside him. They look exactly alike in heights and appearance. Monkey D. Luffy is wearing a hat while his brother is not wearing a hat. The brother that is not wearing the hat has golden brown fur in areas like Sun Wukong. The brother that is not wearing the hat has fur similar to a monkey. The fur is not thick. They look like seventeen years old.