Disclaimer: I don't own Bleach; Kubo Tite does. I do, however, own the idea and plot behind this story.
Setting: Massive AU post-Soul Society arc; massive AU post-chapter 418 for the future timeline.
General Warnings: Blanket spoiler up to the current manga arc, gen with hints of various pairings or ship-teases, English isn't author's first language, un-beta'ed. Don't read further if you're uncomfortable with the aforementioned stuffs.
Prologue - Coming Home
The sun had just risen when he stepped out of the Garganta, painting the early morning sky with soft orange and pink hue. Ichigo took a deep breath; Karakura wasn't the cleanest town by far, but compared to the stale and sandy atmosphere of Hueco Mundo, the slightly polluted air above the town smelt like heaven.
"It's been so long since I've seen the town this peaceful," the Other commented as he walked out of the dimensional tear a few seconds after Ichigo, his hooded traveling cloak fluttering slightly in the morning wind. Ichigo tilted his head back to glance at the older male.
"You said this place was destroyed in your timeline," Ichigo prompted.
The Other nodded. "Ravaged to the ground around four years after this exact date during a skirmish between Milicia Blanca and Wandenreich."
"There was no resistance at all?"
Gold eyes dimmed as the Other's expression turned pensive. "We were caught off-guard and outnumbered. One moment we got a warning about a party of Cazadores entering the town, the next moment several Neo-Quincies also popped all over the place. Swarmed like that, it was either the town or the people. We chose to save the people."
Ichigo's perpetual frown deepened as he took in that piece of information. He yelped when the Other suddenly flicked his forehead, apparently sensing the change in his mood.
"It won't happen," the Other said with firm certainty, ignoring his grumble. "Wandenreich will still declare war—that's kinda unavoidable considering their feud with the shinigami had already existed even before the founding of Gotei 13—but there will be no army of Neo-Arrancars messing things up even more, and you'll be prepared this time around."
"You mean we will be more prepared," Ichigo corrected, a bit miffed with the Other's self-exclusion. "We, because you'll still be around when the time comes."
The Other stared evenly from under his hood. "If you say so."
"I do say so," the younger of the two said vehemently. "You're not going to vanish anytime soon. Urahara-san will find something to help." He reached out to grip the Other's cloak. "This is supposed to be your second chance, and it's only fair that you get to live through it. After all," he smirked, "if I were you, I know that's what I would want, after all the problems I went through to go back."
The Other gave him a long, flat stare for that remark, before snorting and looked away. "Smart-ass."
"Takes one to know one," he shot back.
That comment earned him a rough ruffle on his head. He growled and swatted at the older man, but the Other easily twisted away and vanished in a string of consecutive shunpo, heading toward the northern side of the town where he knew Urahara-san's place was located.
"Bastard," Ichigo grumbled under his breath, before breaking into shunpo of his own to catch up.
Milicia Blanca (白死軍団; Legion of White Death): An army under Aizen Sōsuke's command.
Cazadores (狩猟隊; Hunting Force): A branch of Milicia Blanca whose primary function is to root out and capture soldiers from opposing forces.
Short prologue is short. I've tried to make it longer, honest, but it didn't want to cooperate.