A/N
Ok so I decide to go with the AU After Ichigo beats Grimmjow here is most of the important back story.
Tatsuki gazed out the window on the passenger side of the cruiser as her partner drove them back to police headquarters. Her mind was wandering over the past ten years. Everything had started with Rukia's disappearance. It was only after Inoue Orihime's kidnapping that she had been let in on what exactly was happening in her friends' lives. With the threat of Hueco Mundo bearing down on them Mizuiro Kojima, Keigo Asano, and herself had begun training in hopes that they could do some thing in the inevitable conflict. After the first year Tatsuki had learned that she could control the wind and began to practice with it. It was in that first year that, former captain of the tenth, Toshirou Histugaya had been exile from soul society because of some bullshit about a kings seal.
After that, maybe 2 months later, an arrancar by the name of Neliel Tu Oderschvank had come to Karakura in tears and begged Ichigo for help. That's was the first time the force of Karakura truly faced the consequences of war. Ichigo, Toshiro, Yoruichi, Tessai, Neliel, Shinji, Lisa, Chad, and Tatsuki had bust in to Hueco Mundo to raid Las Noches and save two arrancar by the names of Pesche and Dondachakka. They didn't make it. They were intercepted less than 2 minutes from their primary objectives by 3 Espada. The Primera Coyote Stark, the cuatro Ulquiora Cifer, the septima Zommari Rureaux and two dozen numeros. Ichigo charged Ulquiora while Shinji fought Zommari and Toshiro and Yoruichi double-teamed Stark leaving Tatsuki and the rest to deal with the numeros and push on to the target. Of course by the time they got there Szayel had killed the both Pesche and Dondachakka as punishment for interrupting his experiment Neliel went ballistic but Ichigo managed to drag her back through the Garganta with everyone else to safety.
Still in battle Tatsuki had been almost useless, she upped her training at the expense of everything else. Tatsuki's plummeting grades had gotten Ichigo to think about the future of him self and his friends. That was when he had decide that if they only focused on fighting then they needed a job where being able to fight made a big difference. But no one could figure out what until Tatsuki's brother had gotten shot in a local yakuza turf war. Many had wanted to join the police force, I mean hell they were already Karakura's defense force, stopping mundane crime was just an add bonus. But the police were time consuming, had regulation, and operated in the open where they could use their powers freely. There was however a decidedly more shrouded side of the law, that just so happened to be more concerned about combat strength and had equal if not greater influence over the crime in Karakura. So Ichigo started a yakuza, half of his friends were dead anyways so there wasn't too much risk and beating the snot out of various yakuza operation was very good at relieving stress. Tatsuki hadn't wanted to join she still wanted to be a detective and want nothing to do with the world that had nearly killed her brother. Ichigo didn't mind and told her to go for it but to try to avoid cases involving their friends. So Tatsuki began to study again. And that was how things went for a while, studying, training, stopping other crime syndicates, but nothing last for ever.
Five years ago Aizen had brought the full force of Hueco Mundo down on Karakura. The ten-day battle is know by everyone; spiritual or otherwise, as the "war of the shade" to the humans it was a battle whose every detail remains shrouded. Who was fighting who? Why? How? And why are we unable to find any clue as to answer these questions? To the soldiers on both sides its name came from the sheer number of hollows that filled the skies over Karakura and blotted out the sun until the final day of battle.
Naturally in preparation for the battle, defense systems were set up and while they reduce collateral damage and gave the defenders and the Gotei 13 a major advantage it still did nothing to turn the tide despite the full force of the Seireitei in support the battle went poorly. No, poorly does not encompass the sheer impossibility of victory. They were doom, utterly and completely. Captains in full bankai made no difference. It was a lost cause. So when, after 5 days, captain-commander Yamamoto ordered a full retreat and told the Kidou Corps and research institute to fire the inter-dimensional cannon at Karakura to prevent Aizen from achieving his goal, no one not even Ichigo and Orihime questioned or criticized the order, because, as much as they hate it, it was still the right call.
That didn't mean that they or anyone else from the Karakura side even considered following the order, but hey it was their home. As for Aizen it would take him 6 days to create the kings key in Karakura and only 3 for the Gotei 13 to fire the cannon. Ichigo never being one to let others harm his family, whatever the reason, of course planned to bust into the Seireitei and destroy the cannon before it could fire. Naturally Aizen, who would be damn if he let the Seireitei snatch his victory away from him at the last moment, planned to do the same. This mutual goal formed one of the most unusual alliances in the history of all three worlds.
In the living world they were enemies and the battle would continue. In soul society they were allies and would work together to achieve the same goal. Aizen agree to use his forces as a distraction and let Ichigo lead the infiltration force.
Just to get past the kidou defenses of the Seireitei Aizen had to divert almost all of his forces leaving only Gin, Harribel, and low level hollows to continue the assault on Karakura. He also added 4 of his Espada to the Infiltration force. That had previously consisted of Ichigo, Neliel and Yoruichi with Urahara commanding the defense of Karakura. The team consisted of 8 members, Ichigo, Neliel, Yoruichi, Yammi, Grimmjow, Ulquiorra, Stark and Lillynette, with Tessai briefly disabling the kidou defenses to allow the team undetected entry to the Seireitei.
The battle raged for another five days. The force of hollows that were bearing down on Seireitei was so great they had to remove members of the Kidou corps from operating the cannon just to make sure the defense system could would hold long enough for them activate it. But in those five days a full quarter of Hueco Mundo's population broke against the pillar of soul society. According to the infiltration team after two days captain-commander Yamamoto order the 5th, 6th, and 7th division off of the western wall so that they could aid the other three battle fronts. He then held the entire western front by himself for 3 days. Yes, he was in bankai and exhausted by the end but that mattered little to the millions of hollows that fell before him.
As for the infiltration team things went well until they ran into Kurotsuchi Mayuri and Zaraki Kenpachi. They weren't far from the kidou cannon at that point and chose to scatter and meet up at the cannon itself. This might have worked against Kenpachi and some of the other captains but Mayuri had his own priorities. Sure he wanted to test the cannon he had help build but he was already sure it would work and he could also build a new one but it was unlikely that he would find another soul that had managed to split itself into two separate but connected entities.
He captured Lillynette and then used her to force Stark to obey him. Ichigo being, well, Ichigo, fought Mayuri and freed both of his captive then he and Stark in full resurrecion killed the 12th division captain and burned most of the R and D institute to the ground. In the mean time, the other 5 members of the team reached the cannon. They where having a hard time destroying it until Ulquiorra used his resurrecion and then some how topped that, (Tatsuki still didn't fully buy that, arrancar were powerful enough without have a 2nd release) and began firing off spirit lances. The remaining four left him to his work and went off to ensure he wasn't interrupted. Neliel dueled Kenpachi, and informed him that she had lost her first family and would not lose another before cutting off his arm and ceroing him into unconsciousness. Fortunately for Kenpachi the cut for is arm was exceptionally clean and Unohana was able to reattach it. Stark and Ichigo caught up with the rest of the group just before Ulquiora finished and they all hit the after burners to get out to there as fast as possible.
Aizen, along with Tessai, was there to greet them as they exited the fortress. Aizen ordered his Espada to kill Ichigo and his comrades. Stark informed that in the Seireitei Ichigo had saved him and Lillynette from a fate worse than death and therefore any debt that stark owed to Aizen was overridden by his debt to Ichigo. Ulquiora was intrigue by what kind of human could fight him evenly, convince so many individual of different backgrounds to join him, and still put aside his fears to work together with an enemy and achieve a common goal. So he join Stark in his defection telling Aizen he thought Ichigo might have the answers he was looking for. Aizen had been so dumbstruck by the revelation that he hadn't bothered to stop Ichigo and his companions from leaving.
At the end of the war the score on a large was as such Seireitei: 2, Aizen: 1, Ichigo's forces: 3, Renji: 1 and Yamamoto Genryuusai Shigekuni: absolute BAMF. The Seireitei had held and Aizen didn't get the kings key. Aizen had prevented the annihilation of Karakura before he could make the king key. Ichigo had stopped the Kidou cannon and save Karakura, two extremely power arrancar had changed side and Urahara's immaculate tactics had turn a devastating lost in to a resounding victory. Though Urahara did mention that Gin had fallen for his trap more easily than he like and seem very lethargic when responding to Urahara's tactical moves. About a week after the end of the battle captain-commander Yamamoto along with all other captains and vice-captains called up Urahara and demanded to speak to with Ichigo. He then demanded that Ichigo inform him of the name of his "organization" so that they could be recognized as official enemies of Seireitei. When Ichigo told him they didn't have a name Renji jokingly suggested 'The Ghost Hunters' and the name stuck. After which Yamamoto proceed to request a formal truce and defensive alliance with The Ghost Hunters against Aizen. Of course, Ichigo accepted.
A/N
If you have an idea about where this plot should go TELL ME! I will write about 4 short chapters before i have nothing else to write. I need new characters to fill vice chaptain positions. Who are the ghost hunters fighting first? Aizen or soul society(the central 46)?should I even focus on the larger conflict or stick to mysteries surrounding The Ghost Hunters in the eyes of Chief Harai and Detective Urashima? I dont know also if you have suggestion for the other plot line that would work to as i may write that as well, it maybe more promising. If I Don't get suggestions then I'll have to abandon this before it even really starts and I don't want to do that.
well thats all for now later y'all
3ndl3ss