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.
The Scrappy: A lot of fans feel this way about Yukino for her actions at the end of volume two.
The Woobie: Surprisingly not Yukino, but Mari's friend Oozawa who has a hopeless crush on Yukino.
Jerkass Woobie: Yukino fits this dynamic pretty well, you feel sorry for her but most of her problems are her own fault and she delves into wangst way to much.
World Of Woobie: Its hard to come up with a character who doesn't fit some form of woobie. Even Mika who is the most successful and emotionally balanced character is alienated from all her old friends and fame is taking its toll on her personal life.