Retsuko is a weird case, she voiced by someone who we only know by a handle, which is Kaolip, she's the wife of the director and it doesn't seem like she's done anything else, which is a shame cause I think she has a really nice voice and I was hoping to check out more of her work. Hopefully she'll do more in the future. Also the director, Rareko dose her voice during the metal signing parts, this part doesn't have much substance or acting to it and it's the only time he's done voice work since he's a director. It works for what it is.
Fenneko: MAL is kinda lacking in info so I'll have to go look at ANN and hope it has more info, usually dose. So for now I'll just cover two more. Fenneko is done by Marina Inoue, she's really pretty, I know I say this about a lot of VAs but obviously a lot of them are, it's Japanese entertainment business after all. Anyway, she's done a boatload and is actually a repeat, since she does Yoko from Gurren Laggan. She's in a lot of things although most of it I haven't seen. Just Yoko and a few others, surprised I've somehow mostly avoided her, I liked her work here.
Lastly I'll do Hiada since these three are kind of a trio, and they all have info on MAL. Better to space these our anyway. So Haida is done by Shingo Katou, who has only done 1 other role and it's a show I've never even heard of despite it coming out last year. At least there's not some WIXOSS conspiracy going on this time. He does alright, but here's the thing, he's good but he seems to either be misunderstanding the directing or the voice director is poor. He's a very good voice actor obviously, but it's just something ever so slightly off, I probs only noticed it cause I care about voice acting so much and am use to a high standard. He's not as bad as the cousin for flying witch at least, haha.