You're over optimistic to think it's not. Accessories are generally made out of hard candy or something similar, and the blade is basically the same. It'll cut through other yukkuris but not people.
What makes you think it isn't? The sword is perfectly matched for the yukkuris size, and it could easily not be a wakizashi as it would have been killed trying to steal it (they don't just fall out of nowhere). The character it was based off uses a sword as well, so it makes sense that it's an item associated with them. In other words, like every other accessory.
Perhaps. I was merely judging by the fact that I don't recall any stories where they had an a weapon accessory as well. For all you know some silly person my have given the youmu the blade. So maybe it's rock candy... maybe it's real. I doubt it's plastic however.
There's quite a few pictures where Youmus have the blade weapon accessories. Only an idiot would waste their money and a good blade by giving it to a yukkuri (I guess that explains your reasoning), so it's most likely it's another accessory. It's also far more likely to be plastic if it wasn't an accessory, as it would end up impaling and killing itself learning to use it if it were real.
There's a lot of discrepancies for Youmu types in general. If the knife is something she grew up with, it'll probably be a sugar-based item. If its something she picks up later in life, it's probably a discarded item from humans. It can be both, stop arguing over absolutes in a yukkuri.
I'm not trying to. I am just trying to explore the possibilities available. Like you said it could be a discarded item or maybe it found it on a corpse or a burnt out old building. I like exploring these ideas. I even acknowledged Tea's point. I find it sad that he still finds it necessary to use such petty lines as
Only an idiot would waste their money and a good blade by giving it to a yukkuri (I guess that explains your reasoning)
You are, and you didn't acknowledge the point in the first place; "you are over optimistic to think it is hard candy plastic" suggests that you think it's definitely not that case, and you were attempting to dismiss it and place your own interpretation as concrete. It was only when you were pressed about it and reasoning provided you back-tracked, as usual.