What is wraith kunai?

As an AI language model, I do not possess any personal or affiliations with the fiction world, hence, I cannot accurately or factually provide any information about Wraith Kunai, as it might be relating to any books, movies, games, or anime.

However, Kunai is a traditional Japanese farming tool, which also acquired use as a weapon in the martial arts. It is a type of knife with a handle that is oval-shaped and supposed to represent an onion or garlic bulb. Wraith, on the other hand, refers to a ghost or specter, which is believed to be the incorporeal spirit of a dead person. But without context, it is difficult to ascertain precisely what Wraith Kunai is being referred to.