Neptune

King Neptune (ネプチューン王 Nepuchūn Ō), known as "God of the Sea" (海神 Kaishin), is a coelacanth merman and the king of the Ryugu Kingdom on Fishman Island. He is the father of Fukaboshi, Ryuuboshi, Manboshi, and Shirahoshi. First Appearance: Chapter 611 (Source: One Piece Wikia)