I wrote this from a prompt on Tumblr that I can't seem to find again about how one person breaks their leg, but their soulmate is the one who actually feels the pain and gets all the bruises and physical symptoms.
Summary: Harry keeps getting hurt but doesn't feel any pain. Louis, however, (his soulmate), feels all the pain as it happens to Harry.
Louis winced as he pressed the cold ice pack against his throbbing ribs. The coldness was nice, but the pressure of the ice against the bruises only added to his discomfort. What was his soulmate doing this time, he wondered?
It seemed like Louis was getting hurt constantly. Last month it was a sprained ankle, followed by a jammed finger, and just today, he was watching TV when he suddenly felt a massive pressure against his chest. It was short and fast, like his ribs had been on the receiving end of a badly pitched baseball. He almost choked on his popcorn as the breath left his lungs and he was jerked back violently against the couch.
After a minute, he managed to get his bearings back and steadied his ragged breathing. Almost hesitantly, he reached for the hem of his shirt and pulled it up slowly, scared of what he would find. The whole left side of his ribs were a faint shade of blue, and judging from the immense pain, he knew it would only get worse.
As Louis iced his ribs, the front door of the apartment flew open. It was Niall, returning from his late-night class. Louis tried to hide the ice pack, but Niall had already seen it.
Niall sighed. "What happened now?" Apparently, Niall had gotten used to his injuries and was now expecting them.
"It's nothing. It's just—" Louis said, and gestured to his chest.
"It's just what, Louis? How bad is it?" Niall took off his jacket and draped it on the edge of the couch before moving to sit next to him.
"I'm okay. It's just a bruise," Louis said.
Niall knew Louis liked to be a bit under dramatic, but in Niall's opinion, these injuries were quite a big deal. Niall moved the ice pack from Louis's side and saw the bruises. Louis glanced down and saw that they had spread. "Man, Louis. This is bad." He reached out a finger and dragged it lightly around the boy's ribs, making him suck in a quick breath. "Hurts, huh?"
Niall looked up to see Louis nod. "A little."
"Do they feel broken? Should we go to a hospital?" Niall asked, completely serious.
Louis had never broken anything before so he really didn't know the answer to that, but he really didn't think it was bad enough, nor did he want to go. "No, I think I'll wait it out, just ice it for now."
"What in the world is wrong with him?!" Niall shouted angrily, which made Louis jump and jostle his side around painfully.
"Who?" Louis asked, holding the ice to his side again.
"Your soulmate! It's like he's trying to hurt you or something. He might be some kind of jerk or maybe he gets in fights all the time."
"You don't know that, Niall," Louis said, wondering why he was defending some guy he didn't even know, but this guy was his soulmate so he felt like he had to defend him. He was someone Louis would marry one day.
"Well, I don't really like him right now. Everyone knows that around this age, you share each other's pain. Any other idiot would be mindful of that and stop whatever nonsense they're doing to protect their soulmate." Niall got up to pour himself a glass of water and offered one to Louis as well.