'youkai' is a collective term for spirits, and they can be of all different types. occasionally they can be neutral beings, and i've worked with a few before. but generally they bring harm to humans either intentionally or by way of life, as in they eat humans like we eat chicken or fish. youkai can be beings who were once humans, and sometimes 'youkai' is used to refer to ghosts too. in my practice, i've mostly dealt with non-once-human youkai.
youkai isn't really meant to be confused with 'mononoke' or 'ayakashi' either, though. φ(￣￢￣ヾ) again, in my practice, a mononoke is a benign spirit of nature; it's more primal. ayakashi form from mononoke when ill intentions or spirit energy corrupt the mononoke, usually by a human. or an ayakashi can arise n its own simply from grudge or regret after the death of a human being when the human cannot pass on. the negative emotions corrupt the soul after death.
...although, mostly i'm explaining how it is in my world. it could be different here. (‘•̀ ▽ •́ )✎
Re: Private
youkai isn't really meant to be confused with 'mononoke' or 'ayakashi' either, though. φ(￣￢￣ヾ) again, in my practice, a mononoke is a benign spirit of nature; it's more primal. ayakashi form from mononoke when ill intentions or spirit energy corrupt the mononoke, usually by a human. or an ayakashi can arise n its own simply from grudge or regret after the death of a human being when the human cannot pass on. the negative emotions corrupt the soul after death.
...although, mostly i'm explaining how it is in my world. it could be different here. (‘•̀ ▽ •́ )✎
i hope this is helping in some way...??