Mohmoo is a giant sea cow. It has a big round nose with a gold nose ring, cow-esque face and horns, green spots throughout its body, and also, due to its seal-like structure, an ability to swim easily.
Even being gigantic, it behaves cowardly, but it is very obedient to whoever controls it. It almost cried when it was ordered to fight the Straw Hats at Arlong Park, but it was warned by Arlong, which made it attack the Straw Hats. Its behavior has not changed even after two years. After seeing the Straw Hats again during the journey to Fishman Island, it quickly fled in terror, but the Caribou Pirates easily forced it to turn back by giving it a lump on the head.
Abilities and PowersEdit
Not much is known about its abilities, but it has a huge appetite that can scare away people.
Arlong Park ArcEdit
When Monkey D. Luffy, Sanji and Yosaku attempted to eat a meal while sailing to Arlong Park, they were surprised by Mohmoo. Yosaku recognized him as a beast from the Grand Line and postulated he was probably hungry. Luffy initially attacked Mohmoo when he though he was going to steal their food but Sanji stepped in and attempted to feed the beast to keep with his oath of always serving the hungry. However, when Mohmoo tried to bite Sanji's hand, he was beat up by Sanji in retaliation. Mohmoo was used to tow their boat to the island.
It was initially scared to face Luffy due to the previous incident and almost forfeited the battle. But, being threatened by Arlong, it tried to attack Luffy, only to be used in his Gomu Gomu no Kazaguruma, where Luffy spun Mohmoo around the area, taking out most of Arlong's forces. Mohmoo itself was thrown out of Arlong Park and in the process was knocked unconscious  making the people watching this astonished.
Two Years LaterEdit
Fishman Island ArcEdit
Sometime after the events at Arlong Park, Mohmoo wandered into the waters near Sabaody Archipelago where it was captured by the Caribou Pirates. They used it as a means of advanced sea navigation. By putting a collar around its neck they could use it as a harness and hook it to the front of the ship, allowing it to pull them.
After moving the Caribou Pirates' ship close to the Thousand Sunny, Mohmoo recognizes Nami, Sanji, and Luffy. It gets scared and swims away, pulling the ship with it and leaving Caribou alone on the Thousand Sunny with the Straw Hat Pirates.
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