Deals with the devil? Sounds like it should be creepy!
* In Chapter 31 when Ciel and Sebastian are at Baron Kelvin's mansion and are having [[DidWeJustHaveTeaWithCthulhu dinner]]. The "circus" show he has a few children put on isn't all that scary... Until we see a little girl on the tightrope fall and we're treated to a panel of her leg and a nice ''splat'' complete with blood squirts. Then we see two other children drag off her headless corpse, leaving a lovely, bloody trail behind. Or how about the child who was a lion tamer that's eaten right on stage? The fact that Baron Kelvin is laughing and applauding makes it all the more frightening. Then he acts surprised that Ciel doesn't like the "show" he had the untrained children put on special for him. It was a pretty disturbing chapter.
** Also, he wasn't just using the kidnapped children to perform in the circus [[spoiler: or turning them into ceramic doll parts]]. He kept more of them locked up underneath his manor, ''trying to recreate the torture Ciel underwent while he was a slave''.
** Thought the manga part was bad enough? Wait until you'll see the anime adaptation. You just have to hear Baron Kelvin's voice once to know he's not exactly sane.
* Near the end of Chapter 32, it seems as though Jumbo took care of Finnian, complete with a [[BoomHeadshot bloodied forehead]]. As soon as he stands back up from the impact, we were then treated with a creepy image of a [[DissonantSerenity smiling Finni]], [[http://www.mangareader.net/102-2045-36/kuroshitsuji/chapter-32.html still with a bleeding forehead.]]
** In the chapter after that, as the circus folk try to infiltrate the mansion, Peter and Wendy try to cut Finnian in half with wire... [[http://www.mangareader.net/102-2048-9/kuroshitsuji/chapter-33.html and Wendy takes a bullet through her head out of nowhere]]. This is our first look at Mey-Rin in her ColdSniper mode, and it's a bit of a shock.
* In the first episode of the anime, a businessman comes to Ciel's house for dinner. At some point, he excuses himself and goes to make a phone call, in which he tells how he sold a Phantomhive factory without Ciel's knowledge or permission and how he plans on getting more money from Ciel. Of course, our favourite demon butler hears this and decides to make him pay by driving the man insane with hallucinations, which are scary enough on their own. When the man finds a place to hide from him--actually the oven--Sebastian ''locks him in'' and turns it on. The calmness of Sebastian's voice is chilling, especially compared to the hysterical pleas for his life from the other man. What's worse is how Sebastian slides the viewing window closed right in front of the terrified eyes staring out.
** That whole scene is scary. The guest is reminded of the horrifying things that happened in Ciel's board game ''as they happen to him''--"bewitched by the eyes of the dead", he sees ghostly faces coming from the portrait of the late Mr. Phantomhive. He runs, only to "lose a limb," twisting his right leg horribly on the stairs. He tries to crawl away from Sebastian, who keeps pace with him easily and taunts him about his slowness with a sadistic smile. And when he is locked in the fiery oven, Ciel's words still haunt him--"your body is burned by raging flames".
* When Sebastian puts on glasses it's a bit frightening! Imagine waking up to THAT hideous sight serving you your morning tea!
** Or, what about that second after Sebastian explained to everyone about Hamlet after they were goofing off? Grell said it best:
--->'''Grell:''' My my, Bassy ''you're terrifying!''
* Ciel's flashbacks. A crazed cult leader stabbing a child in front of you? Horrific. How about a doctor who uses children's bones in his prosthetics stabbing a child in front of you the same way the cult leader did? Really horrific. Ciel got physically sick when he saw the doctor do this.
** It's as bad in the anime, where there's no sign of Ciel having been stabbed, but it's implied by Angela that he may have been raped. The flashback in the 22nd episode is also pretty creepy, with a naked Ciel calmly walking (through some rather eerie white mist) ''on top of'' the piled up corpses of the cultists without any fear or hesitation in his eyes.
** "The book of circus" however gives us a LOT of Ciel's flashbacks, two are even in the opening clip. We even learn why the cultists wanted to summon a demon: [[spoiler: to get enough money to be rich for the rests of their lives]]. Too bad Sebastian thought that Ciel was far more interesting as a contractor.
*** The manga makes this worse. [[spoiler: Only ONE person wanted to have money and power, since he was the only one who thought the sacrifice could actually ''work.'' The rest of the "cultists" were just bored rich folks having fun, torturing children and killing them purely for entertainment.]]
* Drossel Keinz living dolls are terrifying for people with pediophobia (fear of dolls). But also the fact that he himself is a doll is quite the Fuel itself. But the worst thing for pediophobic is the puppet of Drossels "Master".
** For the few episodes he's in, Drossel is loaded with creepy. He decapitates someone on screen, uses jewelry to pick out his victims, and always has that CreepyMonotone along with the IronicNurseryRhyme. One notable bit of terror is when he's talking with Elizabeth on picking a gift for Ciel before he comes to his decision, you get a close up of his face with Lizzy reflected in his eyes.
-->'''Drocell''': It's perfect. We'll give him ''[[PuppetPermutation you]]''.
* ''[[Manga/BlackButler Black Butler II]]'' also has its fair share of horror, but the one scene that tops everything occurs in episode 10. It begins with Hannah talking to Ciel and saying that she has something to show him. Perfectly pleasant, right? Then her mouth opens unnaturally wide to reveal [[BodyHorror this black abyss where the inside of a human mouth would be]]. The eye she stole from Alois Trancy is rooted in the back of her throat, and since Ciel's soul has been partially fused with Alois's at this point, he's basically staring at himself from inside her. Hannah watches calmly while Ciel suffers a [[FreakOut severe nervous breakdown]]. Also counts as ParanoiaFuel, since up to this point the episode made you believe that they were really going to hit it off as master and servant.
* That bit where Claude is brainwashing Ciel into thinking he's Alois and rewriting his past.
** Going more into it, remember that [[spoiler: Alois/Jim was a SexSlave who was raped multiple times by the old earl, not to mention it was implied that he was probably forced to prostitute even before hand to survive. This basically means that Claude figuratively AND literally [[MindRape mind raped]] Ciel.]]
*** The above makes [[spoiler: Claude's interactions with Ciel while he was Ciel's butler]] all the more creepy than they already were.
* Episode 1 where Alois [[EyeScream stabs out Hannah's eye with his fingers]].
* Angela/Ash during the last two episodes of season one. ''"[[MadnessMantra Every one...every one...every one, every one, every one, every one, every SINGLE LAST ONE OF THEM BE CONSUMED BY HELLFIRE.]]"''
** complete with nightmarish computer glitch-like transition between Angela's face and Ash's face. Oh man. And this troper thought only the When They Cry series could get that creepy...
* Ciel's LaughingMad moment at the end of the Circus arc in the manga is terrifying, especially considering how reserved he generally tries to be. After a massive PTSD attack in Kelvin's mansion and [[spoiler: arguably crossing the MoralEventHorizon by burning down the entire mansion with uncountable innocent kidnapped children inside]], discovering it was AllForNothing makes him... laugh, and laugh, and laugh, and babble about how humans are revolting and desperate and "[[HumansAreTheRealMonsters even more demonic than a demon]]", and how he's the same. And as the ribbon off his hat is stolen by the wind, you remember that [[TearJerker this is a thirteen-year-old kid]]....
* Any time the [[OurZombiesAreDifferent bizarre dolls]] show up. Especially [[spoiler: when they start acting more human- and begin repeating the same lines over and over.]]
* The werewolf curse. First you cry, then you get rashes, your nose starts bleeding uncontrollably, your face swells up, until eventually you die in agony.[[spoiler: Even more terrifying when we learn that the "curse" is actually the effect of inhaling a toxic gas, made by the villagers. And Siegliende was needed only for completing a formula for making the gas even more deadly]].
* The story of how [[spoiler: the P4 killed Derrick.]] First of all, [[spoiler: [[AdultFear his death is covered up and his family thinks he's still alive for a full year after his death.]]]] Then he gets turned into a zombie[[spoiler: - a semi-intelligent one who can still move normally for a few seconds before it starts eating humans.]] Finally, there's what [[spoiler: Derrick himself was dong to deserve his death. Torturing other kids along with his friends, and he even says they do so just to [[ColdBloodedTorture "let off some steam."]]]]
* We never get to see Sebastian's demon form in full. Judging by his mostly-offscreen NoHoldsBarredBeatdown of Ash/Angela, [[NothingIsScarier what he looks like and is capable of doing is probably pretty damn vicious]].
* [[WhamEpisode Chapter 94.]] The second half. [[spoiler: Sebastian finally snaps. However, it was probably just an act as we see in Chapter 95 (though Sebastian did say he was 90% serious about it...and probably ''would've gone through with it'' if Ciel hadn't snapped out of his BSOD right then and there.)]]
* Mr Phelps' sudden close-up during the conclusion of the ''Mystery Murder Mansion Arc'' [[spoiler: when Sebastian relates how he heard the snake and checked in the room, Phelps was begging for help and foaming at the mouth]].
* During the ''Campania Arc'', just the faces of the Zombies/Bizarre Dolls at times... especially unsettling how wide they open their mouths, if not weird movements like walking backwards or contorting themselves into weird shapes.
* In ''Book of Circus''[='s=] fourth episode, [[spoiler: we watch the circus members' abduction of a young girl, which seems to involve some sort of drugging or hypnosis (possibly by using MindControlMusic) that causes her to hallucinate. The police try to stop them, but are killed by the circus crew.]] What really makes the scene stand out is how [[spoiler: the girl sees the policemen as cute bears that "bleed" confetti. While the deaths we see for what they are are quite bloody, [[GoryDiscretionShot most of them are seen from the girl's point of view.]] It's quite unsettling to hear her laughing and clapping her hands in delight as the "bears" get offed]] and then happily entering the "Carriage to the Dreamland". It's even worse once you learn where the "Carriage" is actually going...
** Now we know that the poor girl was being [[spoiler: kept locked in the basement, in a perfect recreation of the cultist's room where Ciel was tortured. And in episode 9, Doctor used her for his lovely demonstration on how he extracted the material for his artificial body parts.]]
** The anime makes it even worse by giving [[spoiler: every child captured by the Baron matching scars on their foreheads- which implies that they might have been lobotomized, especially since these children are so... uncannily quiet and obedient, not even crying out when they're all '''burning to death.''']]
* Book of Circus episode eight: too many things to count. Let's just say that the episode is way bloodier and creepier than manga. Oh, and Grell is back.
* Book of Circus episode nine, [[spoiler: The last shot of Sebastian while he's engulfing the building in flames. He looks downright ''psychotic''.]]
* Grell's reaction to viewing Beast's death record (''and her "relation" to Sebastian'') can either be absolutely hilarious or absolutely disturbing.
** Speaking of the infamous scene, just how Sebastian seduced Beast can be unsettling to some viewers. They were outside alone at night, he persisted both while she was at a low point and while it was obvious she wanted nothing to do with him, he constrained her to prevent her from fighting or moving while he propositioned her, and then he played her emotionally until she finally gave in albeit while still obviously depressed. [[ManipulativeBastard Manipulation/Pressuring]] at one of its most finest and darkest, and the overall ambiance of the scene (Sebastian's overall demeanor at the time, his prior "incidents" with Beast (getting too close to her crotch without her consent), and Beast's obvious misery during the sex) did not help at all.
** Then there is the "demons seducing humans into darkness" aspect that William/the manga brought up, especially the wording which sounded suspiciously like drugging. While this does refer to how Beast fell for Sebastian's temptation no matter how she felt about/during/after it, another interpretation could be that Sebastian's demonic nature allows for him to know ''exactly'' how to easily and quickly manipulate people to the point they can no longer reason or refuse an offer no matter their initial feelings, using the person's own weaknesses, no less. And even if there was truly no foul play going on, just remember this was all to gain information and Sebastian most likely had a clue on what was going to happen to Beast a little later...
* Doctor, after telling Sebastian and Ciel the whole story behind the children kidnapping, actually had a nerve to ask [[spoiler: Ciel of hiring him! Or recommending him to the Queen because "she's not getting any younger" and "could use some maintenance". To prove how brilliant he is, he made a lovely little demonstration on how he "extracted" the material needed to make artificial body parts.]] Ciel '''snapped'''.
* Chapter 97: The miasma that affected Ciel [[spoiler:is actually [[DeadlyGas a chemical weapon that kills anyone who breathes it in when it vaporizes.]]]] Think about that. [[spoiler:Humans created a chemical gas]] potent enough to affect a demon like '''Sebastian'''.
** Then again, chapter 99 gives a new nightmare moment for Sebastian. He actually suffers no ill effects from [[spoiler:the mustard gas]], as shown when he breathes in an entire room of the stuff and exhales it later.
* Sieglinde got her legs and feet [[spoiler: permanently broken and then tightly bound up]] as a part of "The Ritual" for the introduction of her as the new Green Witch. [[spoiler: The whole werewolf story was entirely made up by the villagers to trick Sieglinde into completing and then giving them the formula for a new chemical weapon, the "ritual" was just to keep her from suspecting anything or keep her from escaping if she ever found out the truth.]]
* The cliffhanger at Chapter 98: Ciel has an emotionally broken Sieglinde alone and [[spoiler: held at gunpoint, forcing her to choose between going out into the outside world (promising that she'll most likely "be used by countless people and experience even worse tragedies than what already happened") or just "get it over with".]] This is also right after [[spoiler: Wolfram was given the order to find Sieglinde and kill her even though it's obvious that he doesn't want to.]]
* Chapter 100 has [[spoiler: Wolfram believing to have found Sieglinde after defeating Bard and Snake, but it turns out that it's Ciel dressed up like her and he's about to shoot Wolfram point-blank]]. It gets worse since it goes into AdultFear territory in that [[spoiler: Wolfram could have understandably assumed that Sieglinde was either long gone, being tortured, or murdered at the time]].
** The satisfied look that Ciel has when it looks like [[spoiler: he killed Wolfram]] can also count.
** [[spoiler: Wolfram nearly shooting Ciel the next chapter also counts, especially with Bard and Snake being within seeing distance but unable to do anything.]]
* The murder mystery arc ends with Ciel and Sebastian telling the young Arthur Conan Doyle exactly what happened: [[spoiler: Charles Gray was responsible for the murders, and they framed someone else anyway (he's a criminal for other reasons).]] When Arthur asks how Sebastian was capable with all of the things he did, Sebastian [[BrokenMasquerade tells Arthur the truth that he is a demon.]] And if Arthur ever tells anyone, they'll be sure to kill him. His last words "we're always watching" [[BeenThereShapedHistory haunt Arthur for the rest of his life and convinced him to continue writing.]] [[ItAmusedMe The only reason Sebastian did that was because Ciel liked his writing.]]
** The anime makes it worse by having Sebastian show Arthur [[EldritchAbomination his true form.]]
** Connected to this, the Book of Murder Side Story could also count if one interprets it as [[spoiler: Sebastian being able to infiltrate Arthur's... or really anyone's ''(including Ciel's)'' mind at will via dreams. Gets worse if one wants to think that Sebastian did that to Arthur multiple times instead of only once.]]
* Chapter 105 once again hints that [[spoiler: Queen Victoria is planning on starting a world war in order to conquer it in the name of England. Not only that, but she might have had some knowledge of Germany's advancements in weaponry and has now obtained its most deadly one by having Sieglinde and samples of it on their way to England.]]
** [[spoiler: Doesn't help that Sascha happily informs that the sulin gas could easily kills hundreds with just a drop of the stuff...not to mention he himself is extremely happy with the idea of a world war happening.]]
* YMMV, but Ronald's character song [[https://www.youtube.com/watch?v=40Avm9ohIMw&index=129&list=PLTeqIaSrJSofjRB43qWmgcebPAo71CE_N Kudoku Kiku Jyanakute]] is fairly creepy. Imagine you're in a club or on the street or anywhere, just minding your own business, and then a complete stranger walks up to you and brightly tells you, [[spoiler: "You have only seven days left."]] And there's ''nothing you can do about it.''
* In Ch. 108, it appears that during the night [[spoiler: Undertaker snuck into Ciel's room while he was sleeping and fed him some sort of liquid from a vial.]] It plays out to have looked like a nightmare, but the possibility of it having been real isn't exactly excused...
** A moment not so much for us but in-verse [[spoiler: for Sebastian of all characters. After the nightmare/the Undertakerís nighttime visit, Cielís contract seal was either flickering in and out or just not there for a while after he woke up. All this work, all the condescension heís endured, and Sebastian was absolutely terrified for a moment that heíd lost his reward and he didnít even know ''how''.]]
** There's also the idea that [[spoiler: the sulin gas might actually come back into play again, given Sebastian opted to hide it in an underwater abyss as opposed to outright destroying it. Not exactly a far stretch to imagine another supernatural being getting a hold of it or something else occurring.]]
* The Blue Sect arc revolves around a cult that welcomes members of all classes, offers free food and education, and even has live entertainment akin to Japanese idol groups. Sounds wonderful (and strange) enough, but in actuality [[spoiler: it is sedating its members during said live concerts and taking large amounts of blood for the so-called masters, leaving a large amount of people (kids included) dead.]] It gets worse since [[spoiler: Elizabeth is currently involved, and it has gotten to the point she has no desire to leave even for Ciel's sake]]
** Ciel's plan to take away Bravat's audience becomes this when it's revealed [[spoiler: he did it to purposely see if more people would die as a result of Bravat having to take even more blood thanks to his resources dwindling.]] Of course Ciel hid this tidbit from the rest of the P5 members, but they will most likely find out eventually.
* Sebastian effortlessly and callously [[spoiler: striking down Elizabeth after she attacked him when he was investigating the sphere hall. Not only was he surprised that he didn't break any of her bones, but he pretty much admitted that if she was not engaged to Ciel he would have killed her.]]
* Entering a contract with a demon causes a marking to appear somewhere on your body (like Ciel's eye). The more obvious/visible the area will give more power and make the contract stronger, all while the easier it will be for the demon to find you. But once you're branded, there is ''no'' getting rid of it, no means of escape.
** To make things worse, it seems that once the contract has been made [[spoiler: if at any moment the demon believes it's contracted is in violation of their end of the bargain then the demon will eat their soul right then and there. Sebastian already demonstrated this in the Green Witch arc, and it could also be argued that, especially during "innocent" moments, he's constantly testing Ciel to make sure his soul is becoming darker and darker.]]