You don't need a Deba knife. Prepare sashimi with seasonal Yellow striped butterfish.It's easy to prepare as long as you learn which part of the knife to use.
A butcher knife for small fish, or all-purpose kitchen knife will work, too!
Use the heel of knife to break off the backbone! Use the tip of knife to cut off rib bones. It's not fun to eat the pin bones so them out pull them carefully.
Enjoy Japanese food around the world.