An arc with only 12 chapters to its name. I wasn't really expecting much, but Gyari's role as an antagonist just turned a generic arc into a "filler arc." NOT BECAUSE SHE WAS GAY (which seems to something the comment section is focusing on) but because she was just a really boring character. A comment mentioned she was static, and repetitive. I couldn't agree more. She's all about being self-imposed, and wanting to marry Kuromu, the unattainable flower. That's it. That's all we know. Other than that she does nothing but self-impose and demonstrate her attitude. We get a 1 chapter flashback that only really stipulates her desire to "want" everything. Something we already knew. Giving her any more than 1 chapter for a flashback would be a bad choice too though, but her backstory just didn't make me invested in her AT ALL. She was just annoying. I didn't Like her, or Hate her (in the good antagonist way). I just really disliked her character.
Otherwise it has it's function as a "basic" arc and could've been as such. Kuromu would take stage as lead actor, this whole arc further cementing her ambition as an evidol (which is basically her special power, rather than her bloodline ice abilities), with Iruma and gang acting as the secondary/supports. Iruma and Amelie both get a moment where they reaffirm their ambitions. Lied was just comic relief (which isn't bad, especially in an arc that should be entertaining > serious). The "twist" development being Wicked Phase Irumi is pretty solid, with it's combination of Wicked phase, a "form" which only occurred once in the series, and Crossdressing. It's just Gyari. She REALLY didn't fulfill her role as an antagonist in a satisfying way, and an antagonist is just as important as the protagonist when it comes to telling an entertaining story that involves both roles.