Hamo / Pike eel from Oita.
13% fat content, so a pretty fatty fish. It contains a good amount of Vitamin A as well.
Between its skin and meat, it has a complicated web of very thin bones that are just impossible to take off. So the technique used here is to put tiny incisions in the meat (together with the bones) without cutting the skin - The skin will then keep the whole thing together from falling apart, and now the bones are cut so small and
they are so thin to begin with, they are completely edible. The technique is called "Hamo no hone-giri", which could be roughly translated as "The bone cutting of Hamo".
It takes a high skill to do this right, as it has to be cut thinly enough to make the bones edible, but not to mince the meat so much as it could then lose its delicate texture and subtle taste.
Hamo is a very prized fish in the summer in Kansai region. It is extremely important in Kyoto cuisine. One of the top 3 important traditional summer festival Gion Matsuri of Kyoto is also called Hamo Matsuri for the custom of eating hamo during the festival.