Megalo

Megalo (メガロ) is a shark that lives on Fishman Island. He is the beloved pet of the Princess Shirahoshi.

Appearance
He has a usual shark design, the only difference is that he wears a shirt from the Criminal fashion line. He is several times larger then the usual shark though is still smaller than Neptune. His mouth is also large enough to cram Shirahoshi into it, but apparently causes great stress.

Fishman Island Arc
Megalo was first seen being freed from the Kraken accidentally when Luffy attacks it. Later, he tells King Neptune about the pirates, and the king invites them to Ryugu Palace, apparently as an act of gratitude. Megalo then carries Luffy and his companions as they make their way to the castle. He is then seen in Princess Shirahoshi's room while the princess and Luffy are having a conversation. He growls at Luffy for making Shirahoshi cry by calling her a crybaby.

Shirahoshi tells Luffy that she wants to go to the Sea Forest. Knowing that Shirahoshi's size will draw attention, Luffy decides to have Shirahoshi stuffed into Megalo. Megalo then leaves the room with the princess inside his mouth while Luffy stands on top of him. As he breaks through the doors, he knocks out several invading pirates.

Trivia

 * His name is probably derived from the legendary sea monster/extinct shark species Megalodon.