Ukitake Jyuushiro, captain of the thirteenth squad in the Soul Society, was not well known for his luck. His family was remarkably poor, living atop a swamp in one of the farthest reaches of Rukongai. His reiatsu just happened to be lightening based, meaning that the entire family had to move on the off chance that he lost his temper or got too excited, quite literally blowing their house to pieces and electrocuting the neighbours in the process. He took ill in his youth with a form of consumption, turning his hair a shocking white, giving him the appearance of a much older man.
During the years he spent training with General Yamamoto his poverty never bothered him, nor did the nature of his reiatsu. Yamamoto's was fire based, after all, and he was in no position to judge. Even Kyoraku, with whom he shared a room in Old Man Yama's barracks, laughed out loud at the stories of his youth and admitted that he wouldn't mind being on the receiving end of an electric shock if it gained him access to a bed in the fourth division, surrounded by pretty girls.
There was only one thing that did not change, that still bothered him and that was how he looked. He longed to have his gleaming black hair back, to be able to chase girls with Kyoraku without them thinking he was a creepy old man. He had tried everything to resolve the issue - hair dyes from the world of the living, treatments in the fourth division, he had even worn a wig for a few months in desperation. None of them had worked: the hair dyes grew out after several months, leaving him with plain white roots, while the wig left him so hot and flustered that he had many dizzy spells and ended up in the fourth division, trying to avoid every 'I told you so' glare from Unohana. It was because of this that Ukitake always remained clean shaven and grew his hair into several different lengths and styles to try and demonstrate how young he really was.
Although their barracks were relatively close together, Ukitake did not have many dealings with the 12th Squad or their captain, save for the rare occasions when they had a joint training session. He did not like to admit it but the other captain put him on edge - he had heard of the crude experiments he performed upon his squad members and Ukitake took great care to avoid it happening to his own. Despite this, he could not deny that Kurotsuchi's science fascinated him, particularly after a peculiar young woman wandered into his barracks late one afternoon. Her name, he learned, was Nemu and she had been created by the 12th squad captain.
This information was what led him to stand outside Kurotsuchi's office door, racking his brains for some way of phrasing what he was about to ask. Surely if Kurotsuchi had been able to create Nemu he would know of some method to restore his original hair colour, though on some level he was ashamed of his problem and preferred not to think of the possibility that he might become a laughing stock afterwards. He reached out and knocked just once. Perhaps the captain would be out and he would never have to ask. He knocked again.
Kurotsuchi was in, not only that, he seemed to be in the middle of an experiment at that very moment. His entire office was filled with orange smoke and he ushered Ukitake inside with the remark that he had better make it quick. Ukitake moved to sit down at Kurotsuchi's desk, thinking better of it when he noticed there was no desk, only an autopsy table.
"Well," piped up Kurotsuchi. Ukitake noticed that he could not see him in the smoke. "What is it you want?"
"Errrrrrrr," he started, scratching the top of his forehead to try and disguise how embarrassed he really was, "the thing is..."
He proceeded to tell the 12th squad captain all about his woes with his hair, how he had noticed his genius and wondered if, by chance, there was something he could do about it. The fact that he could not see him or his reaction made it easier to explain. He heard the other captain sigh irritably, followed by the noise of a cupboard opening and several glass jars crashing into each other. He was outside the office once again with a vial in his hand before he knew it.
"Just one thing," said Kurotsuchi before slamming the door shut. "You must take a mouthful of this every four weeks and only that. Any more and the side effects will be beyond my capabilities."
Ukitake hurried back to his own barracks and locked himself inside his office, pulling the cork out of the vial as soon as he sat down. He took a single long gulp and wiped any excess fluid from his lips. The liquid inside the vial was a murky colour, quite befitting of its taste, which was an odd mix of liquorice and vinegar.
The next day he woke to find his raven hair restored. When Kiyone brought him his breakfast she dropped the tray and squealed, believing for a moment that something terrible had happened to him. When Unohana saw, she insisted on running her fingers through it to check it. Ukitake believed she was quite hurt that he had thought her own treatments were so inferior that he was willing to put himself in Kurotsuchi's care.
The next few weeks were blissful. Despite Kurotsuchi's warnings, Ukitake did not notice any strange side effects other than the occasional itch to his scalp. He sent Kurotsuchi a bottle of sake as a sign of goodwill, though the other captain seemed not to notice the gesture. As the fourth week approached, he noticed white appearing amongst the black and took a second of dose of medicine.
The second, third and fourth dose worked just as effectively as the first, though he could not help but notice that the colour lasted less and less each time. White strands appeared as early as one week along and he wondered if he was becoming immune. When he came to take the fifth dose, his hair returned to white after a mere three days.
Kurotsuchi's words echoed in his mind, that he should not take the medicine any sooner, but he could not stand the thought of looking as he had before and swallowed the rest all in one go. For the rest of the night the itch on his scalp increase in severity, culminating in a terrible headache, but he did not complain, for his hair had gone jet black. Instead he went to bed, working out a way to explain to Kurotsuchi the next morning.
He was woken the next day by the sound of Kiyone dropping another breakfast tray, spilling tea all over the floor in the process. He climbed to his feet to try and show her that there was nothing to worry about, all the while wondering why she was still shocked by it after all of that time. Sentaro arrived seconds later and his reaction was much the same.
"You two," said Ukitake, smiling in his usual way. "What's the matter? You've seen me like this before..."
Neither Kiyone nor Sentaro said a word and Ukitake sighed before reaching for a mirror. Perhaps his hair had gone a different colour or fallen out. Whatever it was, he felt they were overreacting. When he saw his reflection, however, he dropped the mirror and screamed louder than either one of his vice-captains. His hair was black, yes, but he also seemed to have acquired an extra set of ears - fluffy black cat ears at that.
And so it was that Ukitake sat in Unohana's office recounting everything that had happened while she scanned her books and glared at him every time she turned a page. She did not have to say a word; he knew she was angry with him.
"Please hurry," Ukitake complained, his cat ears twitching. "I'm starting to itch...elsewhere."
He glanced forlornly at his rear.
Needless to say, Ukitake never asked for Kurotsuchi's help ever again.