One piece: "The Monstrous Crewmate"

" 𝙹𝚞𝚜𝚝 𝚛𝚎𝚊𝚕𝚒𝚣𝚎𝚍 𝚝𝚑𝚊𝚝 𝚖𝚢 𝚍𝚎𝚜𝚌𝚛𝚒𝚙𝚝𝚒𝚘𝚗 𝚊𝚗𝚍 𝚝𝚊𝚐𝚜 𝚏𝚘𝚛 𝚝𝚑𝚒𝚜 𝚜𝚝𝚘𝚛𝚢 𝚠𝚊𝚜 𝚗𝚘𝚝 𝚜𝚊𝚟𝚎𝚍, 𝙸'𝚕𝚕 𝚓𝚞𝚜𝚝 𝚖𝚊𝚔𝚎 𝚒𝚝 𝚊𝚐𝚊𝚒𝚗. "

When Y/N was found as a small child in the sandy beaches of dawn island. The villagers were skeptical about his origins, kind, and what will he become when he grows up. Only a few took care of him, while others did not

As he grew up. The villagers realized he wouldn't become a beast, more like a lost child, in which they lost their family

As the years go by, Y/N grew. He meets a villager boy, named Monkey D. Luffy

As a few more years go by, a pirate ship docks at their harbor. The pirates made it their base, they called themselves " The Red-haired Pirates". And they, especially the captain. Saw something in him

Join Y/N with his pirate captain and sworn brother, Luffy. To their adventure of becoming great pirates of the sea. And meet their crewmembers during their voyage