Trying to describe the knife won't be easy but I will try and I will post some poor pictures since that's all I have.
This knife has a blade that is folded at a 90degree bend so that it has two sharp edges that would slice at the same time. The blade is 'folded' and level with the handle. The sharp blades come to a point at the tip of the knife. The idea of it made me think of making watermelon look like this picture as a plausible purpose of it.