Being the official Ice Keeper of Arendel (and the only), Kristoff had a pretty big edge on the business. But it wasn't as boring as it sounded, and certainly not as safe either. Kristoff was always cautious in his work, but sometimes he even screwed up himself. Usually he could patch himself up and tough it out through the day until it got better. But the day he saw the baby Anglerfish was the day he needed someone else (besides Sven) to help him through his torment.
It was summer time, so ice was at its highest demand in the year. Kristoff was up in the North mountain area, where the only ice was left during this season. With just him and Sven, it was a slow process but they worked hard and always made the quota at the end of the day. The process of obtaining the ice was like this: Kristoff would take a saw specially designed to cut into ice like a knife through butter. He would have to do this on a lake, so that freshwater is underneath so as to not continuously be cutting down forever. Once the ice block is floating, he would either use a plier-like device to pick it up and put it on the back of the sleigh or, if the block was too big, he would tie a rope around it and tie the other end to Sven who would then pull it out. The duo would do this until they had a sizeable stack of ice blocks in the back of the sleigh and then they would go down to Arendel and receive their payment.
In the later half of one of their many seemingly-alike days, Kristoff was just tying a rope around one block that he had judged with haste. The other end was already tied to Sven, who was ready to pull with all his might when Kirstoff would give the word. Kristoff himself was on the floating ice block, which wasn't as shaking as much as you would think plus he has great balance with doing it almost all the time. While he was kneeling and securing the knot around the block, Kristoff saw something he had only ever seen pictures of. A baby Anglerfish was swimming nearby! Kristoff knew enough to know he was in no danger, he was more in awe. Once the baby Anglerfish hatch, they swim to the top of the waters and feed on plankton. But, Kristoff thought to himself, aren't Anglerfish only found in the sea? This is a lake! But as Kristoff thought about it a few seconds longer, he realized Arendel doesn't have any records on the depths of any of the lakes up here, and that there is a sea close by and there very well could possibly be an upstream channel connecting to this lake.
The Anglerfish was not something anybody would find cute, but it was still fascinating to look out. Kristoff was so caught up in the moment, he stuck his finger out to touch it. Unfortunately, Kristoff did not know that Anglerfish were not the kind of fish that would swim away from a touch. They were the kind that would fight back. So as his finger reached close, the baby Anglerfish didn't even hesitate before it jumped and sunk its tiny teeth into Kristoff's tiny finger. Kristoff let out a primal scream mostly out of surprise from the ferocity of the little creature, but it was a loud enough scream to make Sven think that he needed to pull fast and hard. Sven did just that.
The tug of the ice block threw Kristoff off balance and though he tried his best to stay on, he didn't. On the way down to the icy water, he hit his head on a corner of the ice block which knocked him out cold. The dark red blood was clear in the bright blue water. Kristoff was slowly sinking down and probably would have drowned had Sven not rushed to his aid and chomped down on his collar and pulled him out. Sven could tell his friend was not alright by how motionless he was and the paleness of his skin and the blood still coming from his head. Sven dragged his limp body to the sleigh and quickly tossed him in the best way he could.
Ditching the ice blocks, Sven ran down the mountain as fast as he could until he reached the castle grounds, where guards stopped the familiar reindeer to see what the worry was. When they saw the body of their esteemed Ice Master, they quickly took his body and carried it into the castle's infirmary and put his bed right next to the room's fireplace. Knowing he was a good friend of the Queen and especially close with the Princess, the guards notified those two immediately.
Anna ran in and immediately dropped down by his bed size, squeezing his hand and crying.
"Anna, maybe it's best if you let the doctors do their work now" her sister said. "Hell no" Anna stated firmly. There was no negotiating with her in this situation, and Elsa knew it. So she let Anna stay at Kristoff's side all throughout the night. Even when the doctors bandaged him up. Even when they promised her he would be fine. Even when Elsa told her she could sense the coldness leaving his body, and that he was in no danger of hypothermia anymore.
She stayed with him all night.
Surprisingly Kristoff was the first to wake. It was the middle of the night, and he took in his surroundings. The first thing he noticed was Anna, and he didn't even care looking at anything else. Even the sight of her sleeping warmed his heart, and he certainly felt like he needed a lot of warmth right now. Anna was asleep on his forearm, and as he moved it slightly she sat bolt right up.
"Kristoff?!" she whispered, wondering if he was really awake. "Yeah, I'm fine babe" he said as an answer to the questions he knew she would ask. "Oh God I was so worried Kristoff I was so scared when I got the news I thought what if you didn't wake up I thought what if you had been soaked for too long I thought what if the doctors were wrong and-"
Before she finished Kristoff pushed his lips into hers, knowing it was a good way to help her catch her breath. When he pulled back from that slow kiss, Anna took a deep breath. "Anna," he said, "it's okay. I'm okay. Everything is ok" and he gave a smile that made her feel like the center of the universe.
Without even thinking about it, Anna crawled into the medical bed with Kristoff and got under the covers and snuggled up. "…you still feel cold." She mumbled into his ear. "Well stay here and maybe you can warm me up."
And so she stayed with him all night.