It looks like something possibly from Parker Cut Co. I think swell-center half whittler is a good description.
It is a coke bottle, or swell center, pattern not sure which.
The pattern is what is normally referred to as a "tuxedo" pen. The jigging on the bone says to me that it is of Japanese origin. I have seen a lot of knives marked "Stainless Steel" that were Japanese. If I had to guess I would venture it was likely made by Mitsuboshi.(not Mitsubishi the car maker).Here is an example of a Japanese made tuxedo with very similar bolsters and a Mitsuboshi miniature multi-blade with the characteristic jigging.
I don't name the patterns, but half-whittler is certainly a valid term according the companies that manufacture them. It refers to a two-bladed whittler rather than typical 3-bladed whittlers with two secondary blades. Swell-center whittlers are all equal end as well. They swell in the center of the frame, not to one side, and that is why they are named as such. Tuxedo knives are typically gentleman's knives with very thin frames and shallow blades similar to pen knives, not a full clip and sheepsfoot blades as whittlers do.The knife at the top of the picture below is a swell-center whittler.(Image removed from quote.)
I don't name the patterns, but half-whittler is certainly a valid term according the companies that manufacture them. It refers to a two-bladed whittler rather than typical 3-bladed whittlers with two secondary blades. Swell-center whittlers are often equal end as well. They swell in the center of the frame, not to one side, and that is why they are named as such. Tuxedo knives are typically gentleman's knives with very thin frames and shallow blades similar to pen knives, not a full clip and sheepsfoot blades as whittlers have.The knife at the top of the picture below is a swell-center whittler.
I think I may have to clarify what I posted before.First of all I have never heard the term "half whittler" used before. If you say that certain companies use that term then I will take your word for it.When I stated that they usually swell only on one side I should have said either the top(spine)of the knife or the bottom(well)of the knife.I am posting some examples of what I meant.
I guess it all boils down to a matter of semantics.A lot of people do not consider a knife to be a true whittler pattern if it has a pen and a manicure blade as secondary blades.