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.
YMMV: Tasogare Otome X Amnesia
Adaptation Distillation: Some of the manga chapters have not been included as episodes, and one character, the school nurse, Takamatsu-san, has been written out of two stories entirely.
And whatever the music is that plays towards the end of episode 8, where Niiya finally gets himself together and heads back to the clubroom and Yuuko.
Requiem plays in episode 12 when Yuuko fades away.
Esoteric Happy Ending: The manga ends with the HEAVY implication that Yuko dragged Keichi to the other side. Yay?
The epilogue repairs this by showing that Keichi is still alive and that Yuko is still around to be with Keichi. It also ends with heavy implication that they'll spend the rest of their after/lives together without Keichi dying.
Momoe and Kirie in chapter 19, and Kirie towards Yuuko in chapter 20.
The entire Six Year Sakura story.
Moral Event Horizon: Yukariko breaking Yuuko's leg and entrapping her in a basement for her to die.
The bullies attempting to sacrifice Yuuko (the living one, not the ghost one).
Narm: When Kirishima is about to be sacrificed, her captors choose to tear open her shirt and invoke some Gainaxing rather than actually hurt her. For this troper, the drama and suspense was immediately diffused.
Somewhere between this and Tear Jerker, this vision Teiichi has while talking with Yuuko. She wasn't murdered quickly; no, she was apparently sealed up in a basement, with a broken leg, and left to die slowly, in the dark and in pain, tearfully pleading for help.
Oh hi Episode 6. Nice of you to bring back the Human Sacrifice, Murder and Darkess into the anime. Jeez.
Let's not forget Episode 4, where we get our first proper look at Shadow Yuuko with her Slasher Smile as she stands over a sleeping Kirie.
Squick: The author confesses to not being interested in adult women in the commentary on the swimsuits in the chapter 13 omake.
Actually, with the way original Japanese sentence is worded, it could be interpret as "This corner doesn't call for the adult" instead of the Scanlator version of "I have no need for an adult". Which makes more sense since the manga is serializing on a Shounen magazine.