Sebastian, just your typical guy from our world, suddenly found himself thrust into the vibrant and exhilarating world of One Piece. But, of course, there had to be a twist. Sebastian's transmigration landed him in the body of a greenhorn pirate within the formidable crew of Kaido, the infamous Beast Pirates. But that's not all; this pirate had a peculiar Devil Fruit power – the Bat Fruit. With it, he could morph into an ordinary, run-of-the-mill bat. But here's where the tale takes an unexpected turn. Sebastian was granted a system, a shining beacon of hope in a world filled with formidable Devil Fruit users. As he delved deeper into the system's secrets, a whole new realm of power unfolded before him.