These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Complete Monster: Within the context of this series, Setsugetsuka Tennouji definitely counts: Not only was she the one who got Haruka turned into an outcast at her original school by threatening the entire student body and her best friends to shun her, but is more than happy to use Haruka as a pawn in her family's internal war of succession by making her marry one of her relatives in an Arranged Marriage and then using the influence of the Nogizaka family to remove Touka and become the head of the Tennouji family. All this simply because she found Haruka's cheerfulness annoying!