Kuroyume has a lot of trust issues mostly because he believes no one would appreciate a parasitic species.
Sarcastic jerk who loves to be unhelpful.
If he had a story quest, then it would have to relate to the Raiden Shogun since reviving a yokai species would need her permission, especially yokai like Kuroyume. Most likely, the Shogun would not be happy with the pitch: "Reviving an entire species of Nightmare Yokai in the collective dreams of Inazumans," but~ Im sure the traveler, Kuroyume, and Mizuki can try to work something out.
He always carries around his wagasa because he feels more comfortable in the darkness.
Mizuki and Kuroyume are both on neutral terms; they are at best tolerating each other, but they do become better acquainted when Mizuki decides to help Kuroyume in safely reviving his species.
Kuroyume made a sarcastic bet with Mizuki and lost. He ended up helping out at the Aisa Bathhouse for a while.
(in the first drawing in this post, it may seem a little ooc of Mizuki to say it so bluntly rather than being empathetic but to explain the context, thats basically the 50th time Kuroyume has nagged her about it XD)
Here are some voice lines I made for him:
When it Rains: “Ugh! this human form is such a hassle when it rains.”
When the wind is blowing: “Kh! Winds picking up. If this wagasa flips inside out again, Im haunting the next artisan who called it weatherproof.”
Good Morning: “Oh great~ its morning… amazing…”
Good afternoon: “Ugh… so bright”
Good night: “Sweet nightmares~”
About Kuroyume 2 Yokai: “Yokai can come in different forms, sometimes their a native species or an almagamation of intense human emotion! My kin is the latter. But I think most humans are confused how my kind operates. We dont give people nightmares, thats a purely human response, we simply need negative energies to sustain our forms and powers. Doesnt need to be nightmares specifically but its honestly the only place thats sustainable.”
About us 1: “Ah, yes our last meeting was quite the final showdown, wasn't it?”
Kuroyume’s Troubles: “I don't think I've stressed enough HOW hard it is to be a nightmare yokai. Imagine being a nightmare dweller in need of a house, just for it to be eaten by YUMEKUI BAKU! And then being labeled as a selfish species! It's hard enough to be a natural dream parasite, but imagine being the ONLY one.”
Favorite food: “Oh yes! I have so many favorite ones to choose from. Why, it's not like I lived inside of a secluded dream for 500 years. What makes you think I’d have a favorite? -sarcasm- ”
About Mizuki 1: "The Yumekui Baku and the nightmare yokai have been rivals for as long as dreams have been around. I personally have no resentment towards that Baku-girl, were both just doing what we do best as far as Im concerned. But if she ever tries to meddle in my business, Im going to make her eat the worst nightmare shes ever tasted."
Receiving a gift III: “Oh… This is purely detestable. Have I perhaps fallen into my own nightmare?”