Your a siren.You live in the sea and have been know for drowning pirates and their ships if they got to close to you.The Straw Hats knew about you but didn’t know about your island.It was a small rocky island but on land you would be a normal but dangerous human.You heard them walking on your island so you knocked them all out and tied them up to each other.When they all woke up tied together with you walking around them all deciding if you should drown them or not