Whaaaaa no kasa-obake?

I am going for the iconic classics this time - depending on how much people enjoy this premise, there may or may not be a part two in the future!

The yokai I mentioned is an umbrella monster x3

That said, you may want to change it to Folklore of Japan or Spirits of Japan. Not everything here is strictly speaking a yokai. Some are kami. Others don't have a definition strictly speaking (nekomata) I essence a kami is a spirit of nature promoting harmony and a yokai is a spirit of disharmony. Meanwhile nekomata is just... A really long lived cat who reached some level of enlightenment :3

Oh, I am very familiar with the Kasa-Obake. ^^

And I actually had to check my Yokai facts to see whether I had gotten anything mixed up. Apparently, the term 'Yokai' is very broad, and while it generally refers to malevolent or at the very least mischievious entities, it can be (and has been) applied to all manner of spirits, ghosts, demons and mythical creatures, including the ones listed above.
I am just quoting Wikipedia here, as I am everything but an expert on the matter. That said, even the original Japanese articles utilise the term Yokai (妖怪) for these four, so I feel like it is not an entirely inadequate descriptor.

Still, thanks for pointing it out - I won't deny that I could have researched the whole thing a little better. ^^

Entirely valid! You're fine, it's a very fine point within shinto, and even that varies by precinct, era, and even temple. Still can't wait to see~

haven't seen too many kappa tfs.. excited!

They are not as popular as they should be, although the few examples I can think of all happen to be remarkably adorable!

I'm just hoping for some kitsune or tanuki action.....

Well, in that case, I have some good news for you - one of those two is actually in the lead right now!

Gasp :0