* Ichigo Kurosaki:
** He cannot stand brothers threatening their siblings, especially if they're the older brother. His [[BigBrotherInstinct philosophy]] is that older brothers are born first to protect the siblings that follow.
** Do not insult the people he cares about and has sworn to protect. It doesn't matter if it's his dead mother, his school friends or his TrueCompanions: don't mock them, don't threaten them, don't insult them and definitely do not rub their fates in Ichigo's face if they're the killer or kidnapper of said person.
** Do NOT render him powerless to rescue people and then force him to either watch them being hurt or, even worse, listen to their dying screams. THAT will make him go ballistic.
** PlayedForLaughs one: Thou shalt not call him a girl or strawberry head, due to [[BilingualBonus his effeminate name.]]
*** Also, unless your name is Orihime Inoue, '''[[FelonyMisdemeanor don't sit on his bed]]'''.
* Uryu Ishida
** PlayedForLaughs: He's so into fashion he even designs clothes. Literal buttons are therefore a BerserkButton of his and can trigger a RantInducingSlight.
** NOT played for laughs. When Mayuri rubbed his quincy experiments, especially the torture of Souken, in Uryuu's face, Mayuri received more than he bargained for when Uryuu's response to explode right into a OneWingedAngel form, that not only turned him into a WalkingWasteland, but also one-shot both Mayuri ''and'' his bankai.
* Orihime Inoue:
** Don't try to kill Tatsuki in front of her. To date it's the only example of her killing intent becoming powerful enough to one-shot the culprit to death.
** A more recent one: do '''not''' attack her when she asks you not to. Even more, '''do NOT attack her when she's healing someone'''. Specially if said someone is her beloved Ichigo.
* Tatsuki:
** PlayedForLaughs: Treating a girl improperly, such as attempting to kiss her will flip her out, especially if Orihime or, worse, herself are the targets of the amorous attentions. The teacher actually thought there was a demon in the classroom when it happened.
** Not PlayedForLaughs: She will beat anyone who picks on Orihime to a pulp. As the second strongest female high schooler in Japan, she'll do a lot of damage, too.
** EVEN LESS PlayedForLaughs: Never do anything that will make her believe you have either betrayed her trust or are lying to her. She will put your head through a window if you do.
* Genryuusai Shigekuni Yamamoto
** PlayedForLaughs: Captains losing their haoris, and worse, not caring about it, [[RantInducingSlight drives the devil into him]].
** NEVER PlayedForLaughs: Do not harm, insult [[spoiler: or kill]] his lieutenant, Choujiro Sasakibe. [[spoiler: It sent him into a long-term state of TranquilFury that eventually blew like a volcano in the most epic ignition of a BerserkButton in Bleach history. He's been called Old Man Genocide by the fandom ever since.]]
* Gin Ichimaru: Cross him and he will spend decades plotting your death. [[spoiler: Aizen's Rukongai experiments made a victim of Rangiku Matsumoto so Gin spent a hundred years plotting Aizen's destruction.]]
* Izuru Kira: His WarIsHell personality makes him very quiet and calm even when fighting. However, bring up Gin, a man he was absolutely devoted to, and he'll sacrifice calm for a quick kill.
* Byakuya Kuchiki:
** From the Arrancar Arc on, as far as his sister's health and safety is concerned, he's a KnightTemplarBigBrother. He will ''kill'' for her.
** The camaraderie of an ally is extremely important to him. [[spoiler: Mess with the bonds between friends and allies, and he'll kill the fool who does it.]]
* Shunsui Kyoraku: He is the BrilliantButLazy ChivalrousPervert who would rather spend his days sleeping, drinking, or flirting. Unless the enemy is stupid enough to take out HeterosexualLifePartner Ukitake right in front of his eyes. Cue his laid-back personality switching to vicious, deadly serious mode.
* Toshiro Hitsugaya
** PlayedForLaughs: He's sensitive about his youth, so he insists on being addressed as "Captain Hitsugaya". This is a problem where Hinamori is concerned as they grew up LikeBrotherAndSister and [[RunningGag she still calls him childish nicknames such as Shirou-chan which she Will. Not. Stop. Doing.]]
** PlayedForLaughs: He loathes his short height. When he's called a midget by the even shorter Hiyori, it tips him over the edge.
** '''NOT''' PlayedForLaughs: He has sworn to protect his best friend and pretty much older sister, the aforementioned Momo Hinamori. Seeing her either mentally or physically wounded will press his buttons. [[spoiler: This is built up over the story until it leads to a catastrophic RoaringRampageOfRevenge when Aizen manipulates Hitsugaya into accidentally stabbing Hinamori.]]
* Ikkaku Madarame: He's BaldOfAwesome and knows it. However, if anyone claims he's bald rather than shaven, they can expect more trouble than it's worth.
* Yumichika Ayasegawa:
** Don't call him ugly. It's not worth the consequences.
** The colour purple is the BerserkButton of his EmpathicWeapon which is supposed to reflect the true nature of its wielder. Yumichika keeps calling his zanpakutou a fake nickname "Fuji Kujaku" (Wisteria-Purple Peacock) because it will refuse to give him its power if he does so. This allows him to fight with a [[WillfullyWeak fake shikai]] and [[{{Determinator}} sheer grit]] that mimics a melee-type zanpakutou because it's taboo in his division to possess a [[CoverblowingSuperpower kidou-type zanpakutou]].
* Mayuri Kurotsuchi:
** Comparing Mayuri and Urahara together will send Mayuri into fits of rage and earn you threats of CruelAndUnusualDeath for your trouble.
** Abuse science for selfish or ignoble ends and Mayuri will kill you. He's a ForScience type of guy and that means he'll kill to protect his vision of it.
** Even better: Do NOT claim that either you're perfect or have achieved perfection. As said above, he's a ForScience man and believes there is ''always'' room for improvement. So Szayel claimed he had become perfect? Mayuri gave him one of te creepiest and most painful {{Cruel and Unusual Death}}s in the whole canon.
* [[MamaBear Tia Halibel]]: She doesn't appreciate people messing with her underlings. TranquilFury tends to be the outcome.
* Ulquiorra: He cannot handle the idea of humans possessing the ability to fight on the level of the Espada or worse, surpass them. He went from emotionless to a raging monster inflicting a NoHoldsBarredBeatdown when Ichigo suggests their growing equality in battle means either Ichigo's becoming more hollow or Ulquiorra is becoming more human.
* Charlotte Cuulhorne
** Do not call him ugly. It's not worth the consequences.
** Do not damage his hair. He will go OneWingedAngel and deliver a NoHoldsBarredBeatdown for your trouble.
* Loly:
** She got it into her head that Aizen was replacing her with Orihime to be his new "favourite". She beat Orihime to a pulp for it.
** Even more so: [[spoiler: if either she or her partner Menoly are either hurt or dead -- do NOT heal or revive either of them. As Hollows born from death, being healed/revived by Orihime was like watching TheEndOfTheWorldAsWeKnowIt or something.]]
* Nel: Don't mess with someone she cares about. She will go ballistic. Goes to show you, BewareTheNiceOnes.
* Yukio: ParentalAbandonment is a huge issue for him. Don't provoke it, he possesses RealityWarper powers and ''will'' use them on anyone who dares.
* Riruka: She cannot handle being compared to a normal human or treated like one. She flips out when it happens.
* Tsukishima is a cold, manipulative asshole who doesn't react with visible emotion beyond curiosity and amusement. [[spoiler: But killing Ginjou, the man whom he owed his life to, flipped him so far over the edge he was able to function with a hole in his chest that was killing him. He died only after his rage and despair were spent.]]
* Anime-only butons that don't ever crop up in the manga, include:
** Ganju Shiba will get angry enough to drive a bucketload of customers out of his store if you mention his eyelashes.
** Mention Aizen's betrayal and Hinamori flies into a rage. Considering [[BreakTheCutie the terrible effect]] it had on her, she can't be blamed.