Spoilers below.

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* Hisoka tied with razor-sharp wire to an upright bed, while being forced to remember the night Muraki raped him.
* Sangatanus feeling-up "Hijiri" ([[spoiler: actually Hisoka in disguise]]), then [[spoiler: brutally murdering him]]. ([[spoiler: because it was Hisoka, a Shinigami, he got better.]]) That entire plotline was massive ParanoiaFuel. Getting an organ transplant? Not usually AFateWorseThanDeath. Having said organ come from someone who made a DealWithTheDevil, and now said devil has declared you fair game? ''Not good at all''.
** [[spoiler:Kazusa]]'s death. We don't see it happen, (though the manga shows us the--thankfully not graphically detailed--results) but we do know that [[spoiler:she [[HeroicSacrifice pushes Hijiri out of the way of a collapsing pillar]], meaning that she was ''crushed to death underneath it'']]. She gets better, but ''still''. Oh, and did we mention that she appears to be [[spoiler:''eight years old'']]?
* The St. Michael's School arc, which was so horribly full of NightmareFuel and {{Squick}} that the author made the next arc as an apology.
* The reason Muraki obsessively stalks Tsuzuki? He wants to put his brother's head on Tsuzuki's body, bring Saki to life, and kill him.
* Muraki in general. Murderer, rapist, driving everyone around him insane, manipulative, MagnificentBastard, a doctor (which, yes, should terrify you) and many who see him (he dresses in white, is pale, has pale eyes and hair) think of him as an angel.
* The possible EldritchAbomination that lives in Tsuzuki's head taking on [[AFormYouAreComfortableWith a face he recognizes]] - his own [[CreepyChild from the past]]. He comes complete with a simultaneous TheReasonYouSuckSpeech and BreakingSpeech hybrid. It's notable to mention that after he speaks to Tsuzuki, Tsuzuki proceeds to ''stab'' Muraki. The dialogue suggests it was the child that goaded (or even forced) Tsuzuki to stab Muraki.
--> In order for a flower to bloom beautifully, something must be sacrificed. Do you understand, Asato? Your life is built on the sacrifice of others.
* Volume 11 of the manga aka the '''infamous''' Kamakura arc, all the way through. There's a ''reason'' it's rated M+. Wait, it's not? ''Well it should.''
** To clarify: [[spoiler:Hisoka's father Nagare made [[DealWithTheDevil a deal with a freaky snake god]] and every night the thing tentacle rapes him. Not everything is shown, but it's pretty goddamn obvious. Cue the BrainBleach.]]
*** Actually... It's worse than that. [[spoiler: Nagare didn't make a deal with Yatonokami. His ancestor wasn't strong enough to kill the god, and instead imprisoned it in his own body. To keep it from escaping and murdering everyone in the village the god has been passed down from father to son for generations, each clan head bearing it - and taking the brunt of the rape. ''This is what would have awaited Hisoka, had he not been raped and killed.'']] Woooooow.
** And let's not forget that [[spoiler: Hisoka's mother was forcibly impregnated by the same demon that constantly rapes Nagare, and Rui's pregnancy with Gods-know-what kind of hellspawn has lasted for at least two years. '''In story.''']]
*** [[spoiler:It's not a demon, it's a ''god''.]] Whether that makes it better or worse is up to you.
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