Prior to this arc, there were two things established very well: One, that Ray is over-powered as the protagonist; and two, that for all anyone knows (including Claire herself) Claire is into men, not women.
Then as soon as this arc begins, the story just tells us āOh, Manaria can use all four elementsā. And immediately, I'm likeā¦ excuse meā½ All characters can only use one element, even the teachers and the schoolmaster. Claire, being OP, can wield twoā¦ and Manaria can just wield fourā½ This feels like it should be a way, way bigger deal than what the story acknowledges. People should be scared or envious of herā¦ but nobody seems to treat it as anything note-worthy.
Immediately afterwards, Claire says that āif she had to be with a girl she'd rather be with Manariaā. What in the name ofā¦ are those the words of a girl who's currently in love with a boyā½ Based on what had been fore-shadowed thus far, she shouldn't even have acknowledged Manaria (or any girl, for that matter) as a potential romantic partner. It could have been fore-shadowed much better; failing that, it could have been salvaged in a number of ways, eg by making Claire ponder the issue more or by having her express affection that blurs the line between romantic and non-romantic. Butā¦ nope.
And finallyā¦ Manaria's actions. For the life of me, I couldn't describe to you Manaria as a character because, wellā¦ does she have any? She does what she does so the rest of the plot can happen; her actions at the whims of the writer, serving only to motivate the rest of the characters for no apparent reason. All in all, it's incredibly lazy writing, or that's how it feels like to me.