Complete Monster/Bleach



""In the end, I hope you remember one thing; any betrayal you see is trivial. What is truly frightening and much more lethal is the betrayal you cannot see." — Sosuke Aizen"

Bleach has Loads and Loads of Characters, but the sheer depravity of a particular few is enough to warrant an addition to this page, and it isn't pretty.

Hollows

 * The Hollow Shrieker was shown to have been a Complete Monster even before he turned into a Hollow. A Serial Killer who stabbed a woman named Shibata to death and got off on it, his greatest regret was being killed before being able to do the same to the woman's young son, Yuichi. After he became a Hollow, he sealed poor Yuichi's soul into the body of a parakeet and lied to him, saying that if he could escape from him for three months, he'd revive his mother - and Shrieker would kill and eat the souls of anyone trying to help the child. He gets a very appropriate comeuppance, however - after Ichigo kills him, he is sent to Hell by Rukia for the serious crimes he committed whilst still alive, because the Zanpakuto can only cleanse Hollows of sins committed whilst being Always Chaotic Evil. Shrieker is the only Hollow seen to receive this treatment.

Arrancars
These are the Bishounen Line for the Hollows. At best, they're likely to be a Jerkass. At worst.... well, keep reading.
 * Szayel Aporro Granz, the 8th Espada. As a Mad Scientist for the arrancar, Szayel likes nothing more than pulling the organs out of people via voodoo dolls and then smashing them to bits. In particular, before the organ-breaking began, he toyed with his enemies' heads by ripping apart one out of two voodoo dolls in half, only to reveal that the only parts that can be felt from a voodoo doll are the toy-like organs on the inside. Beforehand, he had specifically modified his underlings to serve as healing aids - by devouring them whole, he'd be able to heal himself. Now, in regards of what he did to poor Nemu...well, bluntly put, one of his abilities allowed him to invade any convenient host (the petite Nemu) that had maintained physical contact with him during his death, devour Nemu from the inside to reconstruct his original body, horribly enlarging Nemu's stomach and emaciating her to near-death, and then burst fully grown from her mouth head-first, leaving Nemu an anorexic husk, whose condition was so bad that she had to get groped by her father to get healed back to normal. He also averts the trope of Avenging the Villain by stating that he is the younger brother of Ilfort, an arrancar that Renji had killed, but has no intention of avenging him. In fact, he infected his brother with mini-spy cameras in order to gain an advantage in their fight, even comparing the loss of his brother with the loss of a box. All in all, he is so terrible

Shinigami
The guardians of the Soul Society are many things, much of them bad, but rarely are they ever as bad as this.
 * Longtime Big Bad Sosuke Aizen. He manipulated his naive lieutenant Momo Hinamori to be devoutly loyal and supportive of him by adopting a kind professor's facade, and coldly stabbed her while hugging her, nearly shattering her sanity and incapacitating her for well over a month. The kicker? His manipulations were so successful that she still believed he was innocent, even after nearly dying by his hand.
 * Continuing further, several years beforehand, Aizen had forcibly spawned monstrous abominations inside eight shinigami officers to test out his latest experiment, and fully intended to murder every last one of them almost immediately thereafter, and when that failed, deviously placed the blame on several of his superiors instead, thereby prompting the feudal government to (attempt to) exile or incarcerate each of them. What's worse is that, by transforming the eight officers into Hollow hybrids, Aizen had destroyed the officers' chances of ever being accepted back by their friends and colleagues. Knowing that he would eventually have to face Yamamoto, he turned Wonderweiss Margera into an zanpakuto-negating arrancar. In essence, Aizen erased all of Wonderweiss' intelligence, speech, memory, reasoning and emotions so that Wonderweiss could negate the abilities of one person. It's so bad that Yamamoto himself, a hardened veteran of countless scars and battles - is disgusted to the point of actually calling him out on it, Aizen justifies it by claiming that, since hollows (Wonderweiss' species) lack a purpose in life, turning one of them into an autistic doll was his way of giving Wonderweiss' existence meaning, retorting that Yamamoto was the cruel one for killing Wonderweiss and destroying the very same purpose that Aizen essentially forced upon Wonderweiss, who promptly exploded, nearly destroying an entire city almost immediately after his death. Then there's the implications of Wonderweiss not being that willing to do this in the first place.
 * Of course, Aizen managed to beat the rap by being a Magnificent Bastard for the majority of the time.... which makes his act of all the more horrific.
 * Once he became a, his very presence was so powerful that it caused anyone who was near him - many human civilians - to blow up, killing over a dozen civilians, while he casually walked his way through a city, for no reason other than his own narcissism.. When he finally met Ichigo's human friends, he planned to
 * Aizen lampshades how evil he is- he claims to be above such "petty" things as ethics and morality, as he claims they would serve no other purpose than to limit his potential. In fact, this is why Aizen is such a terrifying and despicable person: he sees himself as an Ubermensch who is above everyone else, and is thus exempt from the notions of morality and decency adopted by "lesser beings", even mocking them as useless notions only the weak would cling to. Therefore, in his mind, he has the right to do whatever he wants, since he's so powerful that nobody can stop him from doing so.

Qunicies
The Quincies don't have a very good reputation in the Bleach universe as it is, but one stands heads and shoulders above the rest in terms of atrociousness.
 * Yhwach, the leader of the Wandenreich, is the series' final Big Bad and rivals Aizen in deplorable amorality and atrocities committed in the name of a self-centered pursuit of power. Yhwach's rise to power began when he deliberately killed off all the "Gemischt" and "Echt" Quincies that he regarded as "impure" and inferior, thus disposable, by draining their life energy and adding it to his own power. In the present day, he is on a genocidal campaign to eliminate both all the weaker Quincies and all inferior beings who stand in his way of conquering the world. He tortures and kills two Hollows in his army for no reason whatsoever, then he kills tons of Shinigami in his attack on the Soul Society, culminating in him killing Yamamoto while also showing his belief in We Have Reserves by killing a loyal servitor who did exactly what he wanted anyway! In the next invasion, Yhwach double-crosses his own men and drains them of power to empower himself and his own Royal Guard, leaving them for dead. He also says to Ichibē Hyōsube, the leader of the Royal Guard, that everything in this world is for his taking. It's revealed through a flashback that he's led armies of conquests to kill other Quincies in the past, including the families of his right-hand man Haschwalth and another Stern Ritter named Bazz B. If that wasn't enough, he successfully kills the Soul King, which almost destroys reality, and then absorbs him in order to achieve God-like status. Brutal, callous and unrelenting in his selfish belief that everything exists to benefit and empower him, Yhwach stands as the series' cruelest and most monstrous villain.