One Piece, Volume 6 by Eiichiro Oda

The Straw Hat crew follows a trail to Arlong Park, where they discover that their navigator has been living under the tyranny of the fish-man Arlong and carrying a painful past tied to her village. As truths come out—her betrayal, the debt she’s paid, and the scars she bears—the crew rallies to free her, leading to fierce battles with Arlong’s forces and a climactic showdown in which the captain confronts Arlong to shatter his rule and rescue their friend. The volume focuses on loyalty, sacrifice, and the bond that cements the crew as a family.

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