I think they are, see how the edges are much more shiny than the rest where they have been sharpened, so it can hack well into flesh after getting thrown at a victim. But it’s not meant to come out on the other side, obviously. This level of sharpness is enough to do some damage but not too much so that our hypothetical ninja cuts himself when grabbing one.

I made all of this up as I went along. Though it’s close to the truth possibly maybe. Also I enjoy using the words flesh, victim, damage and ninja. Fountain pens help me be a better person.