Toaru Majutsu no Index Light Novel Volume 19

Prologue: The Uninteresting Exchanges Between Evil-doers — Key_Shop.
Accelerator is sent a job to capture/kill a 'merchandise' dealer. He succeeds and ends up with a bloodbath.

Chapter 1: Goodwill Shall Be Trusted for Now — Dark_Hero.
Etzali (disguising himself as Unabara Mitsuki) had a senpai-kouhai relationship with the Aztec magician after his life in vol 15, Xochitl, and now after that incident she calls him ‘onii-chan’ again after a long time. Motoharu comments that he’s a lucky bastard having a ‘imouto’-type girl, and even better one that’s not blood related. Motoharu also mentions how in the world Unabara can try and pick up a girl from Tokiwadai (Misaka Mikoto) when he already has this girl, and Xochitl starts giving Unabara death glares. Xochitl starts questioning Etzali, saying he better not have betrayed their organization for something like this. Awaki comments that Motoharu and Etzali are wasting time on little girls when they have a job to do (Motoharu was with his maid-sister before meeting up with rest of GROUP) and suggests to have Accelerator stop them, but Accelerator says he has no right to stop this kind of thing (Last Order and all…). Awaki then says she’s surrounded by perverts, but the rest of GROUP replied with the same timing she’s the same since she’s a shota-con (no proof yet though, but she didn’t deny the claim).

GROUP is hired to take a rogue ‘group’ called ‘Spark Signal’ in Academy City, though after Accelerator wiping out their main force, they found they’re after info on DRAGON, and should’ve squeezed info out of them first.

Chapter 2: A Simple, Yet Complicated Question — V.S._Calamity.
Shiage tried to hijack a mini-copter to get to where Rikou is, but the pilot pulled out a knife from nowhere and said aviators these days are tired of being hijacked and they’re not all helpless victims. Though after the pilot heard Rikou and Shiage’s talk on the phone and sees how desperate Shiage is to try and save Rikou she decided to help.

Later Shiage jumps out of a helicopter without parachutes down towards something that he’s not sure it’ll save him from a hard landing, while firing down at 3 guys holding Rikou hostage. True main character style.

The remnants of Spark Signal have 5 members guarding the hostages. Accelerator charged in trying to kill them all, then the 5 got killed off by Sugitani, one of Director Shiokishi's bodyguards. Sugitani was only there to tell Accelerator to stay out of Shiokishi's businesses if he doesn't want to regret it, and then left.

Accelerator then saw Rikou lying there looking pained, went to have a look what's wrong, then Shiage arrived and thought Accelerator is gonna rip her to pieces like he did to Komaba. Shiage then declared even though Skill-out were at fault that time, they had the resolve to do whatever it took so he doesn't blame Accelerator for that, since otherwise it'll be a insult to Komaba, their 1st leader. But Shiage said then if Accelerator want to kill someone who no longer wants to stay in the dark side then he'll take him down. Accelerator knew it's a misunderstanding, but still complimented him for his action and bravery then charged.

Shiage's planning to force Accelerator into a situation where even a bullet will work on him, taken from his experience against Mugino. though Shiage then got blasted back by the air pressure created by Accelerator. Shiage blew apart a passing security robot (the bucket-shaped kind) and threw it at Accelerator, hoping the magnetism from the broken robot will affect the collar Accelerator wears. Before the robot reached Accelerator it got blown away. Accelerator then charged right into Shiage and held him up by the collar, then blew him across the room. While Shiage's crawling up Accelerator told him if he stays down he'll let him live, if he gets up he's dead. Shiage refused to give up, and told him they both have reasons to do what they do.

Accelerator was going to turn Shiage to mush right there, but when he saw Rikou stumbling towards them he told Shiage if Shiage planned to use her as a shield to keep fighting he'll do Shiage a favour and rip Shiage apart. But if the girl gets worse from fighting it'll be troublesome for him, and he'll retreat, saying that's how a villain should do things. Accelerator then manipulated the vectors under his feet and disappeared in a blink of a eye. Shiage finally realised he misunderstood the situation, went to hold Rikou and cursing himself for being so useless. Rikou said Shiage's not useless, since for her he's willing to fight into a building where the Anti-Skills can't. Shiage's not convinced, thinking if it was a 'main character' then Rikou wouldn't be hurt. However he also thinks that though he's not a top-tier villain like Accelerator, it doesn't matter if himself is a punk as long as he can protect Rikou and her smile.

Chapter 3: The Wider Path that is Opened by Destruction — Battle_to_Die.
Accelerator and Awaki both know about Unabara and Motoharu being magicians, though they just think of them as ‘espers infiltrating from another organization and ended up betraying their own’. Accelerator also thought why now that the ‘Level 6 shift’ experiment’s sisters aren’t disposed of yet, he wonders whether the experiment was built to fail from the start.

And as a final piece that shows even Accelerator has mellowed, he told a passing kid he saved before in a hostage situation “I’m the Strongest Level 5, I don’t need brats worrying about me”, just to prevent the kid from rushing in and killing himself accidentally. In addition: “Listen, even if someone is suffering before you, the kind of person that can take up arms without hesitation to shoot down the villain is no better than a villain himself. The kind that doesn’t care about others, doesn’t give second chances; someone that kills is given a reason, is definitely not a hero. You don’t have to become that kind of person. That’s my specialty. Only I have to go through that”.

After some negotiation, Director Oyafune decides to help Accelerator to take down another director, despite earlier having decided to not interfere with the Dark side of academy city due to threats to her own daughter. Oyafune decided even if she retire there’ll always be threats from the dark side so she might as well go and get rid of the root of the problem.

The 2nd district of academy city is basically a giant weapon factory. The director attacking GROUP has his main base hidden in one of the experimental bomb shelters that get bombarded on a regular basis to test both weapons and the shelters. This director’s employees are like a army, and have Capacity Down (they’ve improved Capacity Down drastically, to the point where if Accelerator or Awaki even activate their ability they self-destruct) installed.

Chapter 4
The Aztec organization infiltrated to the point where they are right next to a Director, all for the sake of eliminating Etzali.

Kinuhata Saiai carries around emergency nitrogen supplies in case her opponents create a vacuum around her to prevent her using her powers.

The Aztec organization has gone to the point where they modify all ‘normal’ agents to all carry around a ‘original’ grimoire for battle purposes, and it can’t be destroyed by Etzali’s obsidian knife. The leader of the Aztec organization, Tecpatl, even came himself to eliminate Etzali (I’m not gonna attempt to spell Aztec names…). The leader and Etzali battle, and Etzali manages to make the grimoire turn onto its owner – grimoires have a ‘mind’ of its own and seeks out those who can use them to the fullest, and the leader set up measures to make sure his mind is safe from the dangers all grimoire possess, where the information is too much for the human brain to handle. Therefore Etzali signaled he’ll take on the burden of the opposing grimoire, and let its knowledge flow through him regardless of the cost, and the grimoire destroyed the leader after deeming him not fit to possess a grimoire.

The ENTIRE dark side of Academy City (minus GROUP) knows about Kamijou Touma and his worth to Aleister, including how no matter what kind of mess Touma causes within Academy City it’s all within Aleister’s margin of error, and Touma’s under Aleister’s personal protection. It’s also known Accelerator have something to do with Aleister’s plans, though Accelerator doesn’t have the protection like Touma. Hamazura Shiage however is an unknown factor which not even Aleister can predict, since according to the plans was Shiage was supposed to have died in vol 15 in the fighting between ITEM, BLOCK, MEMBER, GROUP and SCHOOL, but he beat Mugino and survived, something Aleister cannot comprehend. Therefore the entire Dark side of Academy city has got the order of eliminating Shiage directly from General Superintendent Aleister, and the whole city is out to attack Shiage.

Shiage was about to be killed before Mugino intervened, saying she’s the only one allowed to kill him and wiped out the pursuers (which were ex-Hound Dog members).

The director that was after GROUP was defeated, and he said unfortunately he does know the truth about DRAGON, and it might have been better if he didn’t know in the first place. When the 4 of them asked him what is DRAGON, he replied “DRAGON is everywhere. Look, right now it’s behind you”. They thought it was a bad joke, but Motoharu, Awaki and Unabara got knocked out instantly, leaving Accelerator to think that’s impossible, the three of them aren’t that easy to dispatch. The director exclaimed the one behind them that did this wasn’t Fuse=KAZAKIRI like he thought, before being knocked out as well, with a voice somewhere saying of course not – she’s only a piece for DRAGON’s materialization. Accelerator saw ‘it’ speak, but to him there’s nothing seem more wrong than ‘it’ being able to act like a human. ‘It’ had long blonde hair, a slim figure and flowing robes that made it look like a girl. Its face seemed to show all sorts of emotion all at once, but also seemed beyond emotions. It also remarked itself can also be called a ‘angel’, or at least sounds closer to the truth than a ‘extraterrestrial intelligent being’, ‘holy guardian angel’, or ‘the true master of the secrets that shaped modern western magics’, and says he/she’s very different than the angels in the bible. And finally “there are few that reach this point. And it’s because so I’m interested in this, and that there’s value in stating my name… I’m the one who once taught the bare essentials of the necessary knowledge to the eccentric magician Aleister Crowley.”

/Chapter 4/: The Two Monsters that Invite People to Hell — Dragon(≠Angel).
Aiwass exposes the truth behind her appearance. According to her, she is manifested due to the virus code implanted into Last Order's brain and the appearance of Kazakiri Hyouka. However, Accelerator finds this as illogical, as Academy City has been hiding information about DRAGON. Aiwass then exposes the nature of her presence and explains that killing her might save Last Order.

The strongest Level 5 falls for Aiwass' taunt and attacks, although even with the Black Wings fully manifested, Accelerator can barely inflict damage to Aiwass. In a desperate move, he shuts down the Sisters Network with aims to weaken Aiwass and destroys her triangular core. However, Aiwass is still present, and Accelerator faces defeat in her hands.

Meanwhile, Mugino continues her pursuit of Shiage and reveals that she has been kept alive by Academy City's Dark Legacy, a machine that is able to repair bodily damage at astouding speeds. Their chase goes to an abandoned hangar, and Shiage manages to trick Mugino into destroying the entire facility. However, Mugino survives and retaliates. Shiage escapes into a testing room and engulfs the battlefield in a fierce heatstorm.

Shiage then steals a supersonic jet and leaves Academy City using it; on the other hand, Mugino lives from the intense heat and Shiage feels that he and Mugino will meet again.

/Epilogue/: Tragedy is Not the End — Brave_in_Hand.
Aleister listens to Aiwass as it talks about the three boys in the battlefield, namely Touma, Shiage and Accelerator. Aiwass wonders if the heroic deeds the three boys have done over the past few days have affected Aleister in any way, and after Aleister remembers being at the shoes of those heroes, Aiwass leaves for good, promising to return "when things becomes more interesting".

Accelerator has decided to focus of Last Order, destroying any of his past connections with anyone along with his cellphone. Now, he seeks for "Index Librorum Prohibitorum", the last hope for Last Order's recovery.

Meanwhile, Shiage and Rikou lands on Russian soil by parachute. Touma also reaches Russia, and marches on to save Index by confronting Fiamma.