Merry is the butler of Kaya, a wealthy young woman living in Syrup Village in the East Blue. He is best known as the original designer of the Going Merry, the first full-sized ship of the Straw Hat Pirates. His appearance is distinctly lamb-themed: he has curly white hair like fleece, two small horns protruding from his head, and a collar that resembles a sheep’s wool. Over time, his hair grows longer and he develops a light mustache and goatee. Merry is a tall man who is always formally dressed in butler attire.

His personality is defined by unwavering loyalty and a strong sense of duty toward Kaya. He prioritizes her well-being above all else and initially views Usopp, who frequently visits Kaya to tell fantastical stories, as a bad influence. Merry is strict and protective, even threatening Usopp with a gun when the boy tries to forcibly take Kaya away. However, he is also kind-hearted and logical, willing to surrender the family fortune to the pirate Kuro if it means sparing lives. After Kuro’s true identity is revealed and Merry is gravely wounded, he acknowledges that Usopp was telling the truth and changes his opinion of him.

Merry’s primary motivation is to safeguard Kaya and maintain the peace of Syrup Village. His role in the story is that of a supporting ally during the Syrup Village Arc. He provides the Straw Hat Pirates with the Going Merry, a gift from Kaya, which becomes their vessel for many adventures. He also serves as a catalyst for Usopp’s emotional growth, as Usopp’s attachment to the ship Merry designed later leads to a major conflict within the crew.

Key relationships include his mistress Kaya, whom he serves with devotion; his fellow butler Klahadore, whom he initially trusts but later realizes is the pirate Captain Kuro; and Usopp, whom he initially distrusts but eventually respects. Merry’s development is marked by his shift from being antagonistic toward Usopp to becoming grateful for his role in saving the village, and by his survival of a near-fatal attack from Kuro.

Notable abilities include a high degree of durability, as he survives a direct slash from Kuro’s cat claws while still managing to warn Kaya. He also possesses shipwright skills, having designed the Going Merry with detailed blueprints that he created twenty-two years before the events of the series. He is known to carry a pistol and can shoot with reasonable accuracy, though he has no formal combat training.