Gyo, 1

In this masterpiece of marine horror manga, Junji Ito tells us the story of Kaori and Tadashi, a Tokyo couple who decide to spend their vacation in Okinawa, near the sea. After a small diving incident with some sharks, the couple decides to return to Tokyo... But before they can return, they begin to encounter strange fish-like creatures. Furthermore, a smell of death begins to permeate the entire island. What really are these beings? And what is causing the stench?