Moo-cow is originally from the Grand Line and was made a pet by Arlong. He brought the giant manatee with him to East Blue and eventually to Conomi Island. Moo-cow took part in the attack on Goza, devastating it and leaving deep furrows in the city.
Moo-cow first appeared when Luffy, Sanji and Yosaku were near Conomi Island. Moo-cow was attracted by the smell of the food, but Luffy didn’t want to share and gave her a gum-gum gun. Sanji, on the other hand, wanted to offer her some of the food, but kicked the manatee away when she tried to eat him right along with it. The three then used Moo-cow as a draft animal for their small boat. However, off Arlong Park, Moo-cow veered off and swam at full speed towards the shore. While she sank with a bump on the head for the time being, the three flew with her ship towards Zoro and Johnny.
Later, when the Straw Hats stormed Arlong Park, Hatchan summoned Moo Cow. The manatee saw Luffy and Sanji and was about to leave, but Arlong was able to sic her on the Straw Hats. Luffy, on the other hand, grabbed the manatee and whirled it away with Gomu Gomu no Kazaguruma, nearly defeating the rest of the Arlong gang with it.
Two years later, Moo Cow was used by the Caribou pirate gang as a draft animal and navigator for their ship. They had caught the manatee in the waters near Fish Man Island. When she encountered the Straw Hat Pirates again, it was seen that Moo Cow had not yet overcome the trauma she received at the hands of Luffy and Sanji, for she instantly fled, dragging the entire Caribou Pirates ship with her. The Caribou pirates’ attack on the Straw Hats was thus thwarted, and Caribou faced them alone. A short time later, however, Moo Cow turned back with the Caribou pirates, with Surume destroying the ship, freeing Moo Cow from the tow ropes.
- Moo-cow’s body anatomy is illuminated in more detail in One Piece Magazine, Vol. 1. Show image hide
- Momoo’s favorite foods are roasted pig and shark.
- Moo-cow’s original name is a reference to the onomatopoeic sound of a cow: “Moo” (jap. もーもー, moomoo).