This is a quick story, mostly dealing with supernatural horror. It's entertaining but not necessarily a must-read.
Story, 6: Given its short length, there isn't much time for the plot to develop. beyond establishing the dangers of the sea.
Art, 7: There are some body disfigurements in the latter half of the chapter, and some really nice detail on the fishing nets.
Characters, 5: Every is fairly one note. This isn't necessarily bad, since the title is only a one-shot, but no one felt particularly distinguishable whatsoever.
Enjoyment, 5: It was a short read, but it was interesting enough.
Overall, 6: I wouldn't necessarily recommend this to anyone aside
from fans of Ito Junji that want to complete all of his works. There are better Ito one-shots out there.