As the OP hasn't returned I wonder if we adequately answered the question? I feel I should point out the a traditional single bevel knife like an yanagi-ba is created in different versions for left-handers and right-handers. Be sure to order the correct one or he'll have a heck of a time using it correctly. A single bevel knife is generally sold semi-sharpened; the knife must be "opened" (the term used to describe the initial bevel creation, polishing of the blade road and creating of the cutting edge). A Tojiro intended for sale in the West may be fully sharped, I honestly couldn't tell you.
If your friend is cutting a lot of boneless, raw fish the yanagi may be a great choice, provided he's comfortable sharpening it. A sujihiki would probably be more user friendly (it's similar to a Western carving/slicing knife). I initially assumed that you knew what you wanted and merely wondered where to get one. Then I reread and noticed that you asked what one was...
If you have any questions beyond this feel free to ask.
If we're not supposed to eat animals, then how come they're made out of meat?