Zanpakuto... Their abilities and shape are usually a reflection of their wielder's soul. As their relationship grows, and the shinigami learn their katana's name, they are able to utilize an even greater power.
Soi fon glanced up as a light buzzing sound and a giggle heralded the entrance of her manifested zanpakuto spirit. Since the so-called zanpakuto rebellion, the spirits had gained the ability to appear whenever they pleased. She had ordered Omaeda's Gegetsuburri out of the room only a moment ago and Omaeda with him. She had thought that he would finally be able to get some peace.
Setting down her brush, she regarded the diminutive girl for five seconds before finally speaking.
"Well, what is it now?"
"Nani?" Suzemabachi whistled innocently, her chestnut brown eyes glinting mischeviously, eliciting a muffled curse under.
"I acknowledge that many zanpakuto have gained different forms to the one formerly shown to their wielder, but as you have always held a human form, I believe that I'm allowed to be skeptical whereas your behavior is concerned."
At that, the facade dropped like a stinking stone.
"Awww, you finally found yourself a man! I didn't think you had it in you!"
At this, Soi fon could only sigh in a mixture of annoyance and relief, whilst the girlish spirit flitted about, leaving a golden trail of spirit particles in her wake. Indeed, she had found someone, and just the thought of him would occasionally bring a light blush to her cheeks when no one was around to witness said feat. Well, she always had a respect for strong combatants, so was it really that surprising that she'd taken an interest in one of the ryoka?
"It's none of your concern."
The road to their stormy relationship had been rough at first, filled with sharp turns and potholes that threatened to tear them apart at a moments notice. But that was made them positively so endearing to one another. He, with his fumbling curiosity and fits of immature rage, and she, who desired to be in control at all times and was very blunt and up front about what she wanted, which at first, had been sex.
If the saying 'Opposites attract' were ever truer for another couple, then she wanted to meet them. She, unlike the other captains, excluding that bastard Mayuri, had been intrigued by his inner hollow. The occasional emergence of his darker, when she would have to goad him into donning the mask, side made their sparring sessions all the more interesting, and all the more intense.
"But I mean, just look at you!" Suzumebachi all but squealed, her pigtails swaying to and fro as she continued to dart about the room, forcing Soi fon's thoughts, and sleep weary eyes to slowly follow the trail of her zanpakutou. "You're actually, really getting married! I was beginning to think you'd never stop fretting over your precious Yoruichi-sama-
"Will you please stop?! I'm trying to get ready!"
"Don't whine, it ruins a grown woman's figure," Suzumebachi tapped her head lightly as she flew by. Soi fon grumbled and batted at her half-heartedly, before giving up and wrapping herself in her veil.
Ten years and one Winter War later Suzumebachi's spirit was still irritating as ever. After the zanpakutou rebellion, her temperment was still as irritating as ever. Getting married wasn't going to change that, not in a millions years.
"So, so, when's the honeymoon?"
"As I said before, it is none of your concern."
"Well, can you blame me?" Soi fon could only blink as Suzemabachi appeared before her, effortlessly hovering in place. "I mean after all, he's pretty cute, what with that orange hair and killer bod, not to mention-
That did it.
"Eeeek!" Suzemabachi screamed suddenly, and the doorsthat lead down to the aisle were violently blown off their hinges.
The captains, and all the other guests, shinigami, arrancar, vizards, zanpakutou, and groom included turned towards the ruined archway, just in time to see the flirtatious spirit struggling in the iron clad grib of her master, the latter maintaining a very firm grip on the spirit of her sword, despite its best efforts to break free from Soi fon's hold.
"You little twerp!"
"Ow! Lemme go! Stop that!"
Ichigo Kurosaki, slowly taking in all of this fiasco his fiance was causing, sweatdropped, adjusted his bow tie nervously, and exchanged a rueful glance with Omaeda, who actually surprised him by smirking gleefully.
"Have fun on your honeymoon, Kurosaki."
They live and die together with their shinigami. They are zanpakuto.