The sea is vast and mysterious, but it is ruled by the declining murloc clan. This is all because there once was a murloc king - the demon shark Siel Legge. He was powerful, commanded the ocean, and established the murloc kingdom.
But in a mysterious battle, the fish-man king disappeared, leaving only his wife and an infant baby. The throne of the fish-man country fell into the hands of the mermaid tribe.
Two hundred years later, the baby left behind descendants. The fish-men clan gradually forgot the legend of the Demon Shark King and only regarded him as a story.
Siel Zod and his mother depended on each other for life. His father died at the hands of humans. He vowed to rebuild the glory of the Demon Shark and become a new generation of king of the murlocs, so that humans can once again feel the terror of the murlocs.
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This work describes a growth-oriented male protagonist. I don't want to affect the plot of the original work too much, so there will be no plots that differ from the Luffy protagonist group in the original work.