A/N: Toward the end of this fic, I kind of describe the little-known 5th state of matter: a Bose-Einstein Condensate. It occurs when atoms approach absolute zero. However, be warned: I took a great amount of poetic license here! (After all I only learned about this through a PBS special!) Yes, there are many flaws with my description and the situation entirely as I am not a physicist or a chemist (and this is not a realistic fic in the slightest). I kind of took an idea and ran with it. So, if you are a physicist or chemist or a self-proclaimed expert on cold: don't flame me about the flaws in my facts! (Ha ha, flame…no pun intended…seriously.) If you really want to know about the actual phenomenon, there's a link in my profile. Thank you.
Disclaimer: I don't own Bleach.
In the fourth division headquarters, Unohana-taichou was sitting by Hitsugaya-taichou's cot. She was in a quandary. The young shinigami had recently fallen ill. A bug was going around Seireitei and quite a few shinigami were being treated by the fourth division. Hitsugaya Toushirou's case was different, however. He was running a mild fever, a fairly common symptom, and one which would, normally, not worry the fourth division's taichou. But Hitsugaya's reiatsu was reacting oddly to the increase in boy's body temperature. As Hitsugaya's temperature rose, his reiatsu rose, thereby cooling him back to his normal temperature. At first Unohana saw nothing wrong with this reaction, that is, until his reiatsu continued to rise, and the atmosphere around him grew colder as a result. At this point, Unohana was practically shivering from the drop in temperature, and Hitsugaya's reiatsu was rising to dangerous levels.
Unohana called for her fukutaichou. Kotetsu Isane ran into the room. "Is there something you need, Unohana-taichou?"
Unohana nodded. "I need Zaraki-taichou's eyepatch," the calm woman said, though a bit of worry was beginning to show through her normally tranquil persona.
"Wh-what?" Kotetsu asked, flabbergasted at the command.
"Please, Isane-san, we do not have much time." Unohana glanced at the icy captain as the temperature dropped another few degrees.
Kotetsu looked confused, but she followed her taichou's orders and immediately ran to the eleventh division headquarters.
Unohana turned back to her patient and prayed, "Please make it back in time."
Hitsugaya Toushirou knew something was wrong immediately. His fingers and toes were absolutely numb. The next thing he noticed was what really woke him up: he was cold! He was never cold, yet he could feel himself shivering. He'd never yearned for warmth before, and he hated this newfound feeling. He liked the cold. He shouldn't be bothered by it.
His thoughts were banished as he felt the atmosphere become even colder. Hitsugaya attempted to grab his blankets to pull them more snuggly around him, but he was surprised when he realized he couldn't move! The numbness was spreading, leaving an icy burning in his lifeless limbs. It was painful. The temperature was dropping more drastically now, and the young taichou could literally feel the water within him freezing. The ice burned inside of him as it quickly spread. First his fingers and toes froze, then his arms and legs, his torso, and finally his head. He knew his heart had stopped; his blood was literally frozen in place. Every cell within his body was solid ice. Why am I still alive? he thought. His body was obviously dead, in fact he was sure that if someone smashed him with a hammer his body would break into millions of tiny taichou-bits.
But even though his body was dead, his reiatsu continued to grow and continued to freeze the surrounding world. Above him, droplets began to form in the air. Instantaneously a drop of liquid would form, before falling to his body. He couldn't feel the liquefied air hit, but he could hear it making a tiny clink! like a drop of water hitting a smooth, crystalline surface.
Hitsugaya was quickly showered in liquid air, creating a cold pool around his frozen body. He was amazed by his continually growing reiatsu, and the still cooling world around him.
He felt as if he was approaching something, something unreachable yet something he strived for. And as he approached that unreachable limit he could feel changes in the world around him. His very molecules were going through some kind of transformation, a metamorphosis into another state entirely. He was no longer someone or something or even billions of tiny somethings. Now he was billions of tiny…pulses? He wasn't real anymore. His molecules weren't real anymore. They were as insubstantial as light, a mere wave of matter. The individual things began to move together, to synchronize. Eventually he, and the world around him, became one entity – not even an entity – occupying the same space. He continued to approach his limit, his horrible and motionless destination. He was getting closer while his wave of a body existed in suspended time. Closer and closer and closer and…
Kotetsu ran to her taichou, Zaraki following close behind. Unohana turned to her fukutaichou with solemn eyes. "We were too late," she said simply, her eyes becoming watery.
Kotetsu looked startled at the state her taichou was in. She reached to open the door of the room housing the former taichou of squad ten, but she pulled her hand away quickly as the frozen door burned her palm, as though she had touched liquid nitrogen instead of wood.