Somebody's gonna die

CometStorm looked at the clock from his bed in his room - 8:30 pm. Twilight was in the room next door with his newborn half-sister, FeatherBloom
She's never late... Late? HA! When did this become a thing? She just barges in uninvited every evening at 7:00pm on the dot...
He kept glancing at the clock, its ticking echoing in his head as every minute went by. Tick, tick, tick, tick, tickAt 8:45 he closed his book with a loud snap, before opening it hesitantly again. 
Why should I worry? She could just be home doing nothing... It doesn't matter. Who cares? I don't.
But no matter how hard he tried, he could get the sickening feeling in his stomach, this time not from off food. He sat up before lying back down again, repeating the action a few times as he struggled internally with his pride. 
I'm just going for a walk, nothing else. He convinced himself, getting out of bed and walking a little too fast out of the castle.
The moon had already risen high into the sky, and his hooves led him on a race to the beach, the first place he thought of when he thought of her. He ran until his lungs burned, but he felt a tugging in his horn that lead him onward, away from any stubborn pride he had left. As he raced onto the beach, the tugging suddenly stopped and he felt a lightness which made him dizzy. He looked around frantically, trying to remember which places she loved to surf, which way she would run, which set of rocks she would jump over. Desperately, he waved his head around, aiming his horn in every which direction for some kind of sign. It was only for a split second, but he saw it. His horn glowed, only for a moment, but it glowed. He started running towards the right, with the rising tide soaking the fur around his hooves with salty water.
Then on the beach, he saw a figure on the sand in the moonlight. He instantly recognised to the soggy, blonde mane covering her head. OceanSong
Slowing down, he came to a stop by her and leaned down, nudging her. The petals she used for her flower crowns stuck out of her hair in a mess, but the flower crown was long gone.
"Shorty? Hey, this isn't the best place to sleep" he teased nervously.
He breathed as she slowly raised her head, but his stomach dropped as he saw her face. Tears stuck sand to her face, the eye covered by her hair was swollen and bruised. 
"CometStorm?" she whispered, smiling weakly at him after a second. Dropping down, he pressed against her to share her weight as she struggled to get her legs under her body. He saw her legs shaking as she tried to stand up.
"Shhh... don't, just sit" he soothed, feeling a wave of affection looking at her. Always so cheery, excited to see him, bouncing around, smiling, this was the first time he had ever seen her like this.
He gasped as he saw the bruises on her body, sand was plastered to her body and her hair was a mess. But that wasn't the worst of it. Standing up awkwardly from her back was her wing, bend in an awkward shape, her feathers in disarray and her whole body trembled.
"What happened?" he asked gently, watching her face as her lips trembled.
"I-I was surfing, and I was coming in to go see y-you. And s-s-some other surfers followed me as I was paddling in. T-they grabbed my board and pushed me off..." she trailed off, looking up. Following her gaze, Comet saw her board, splintered into pieces and he felt his heart squeeze. He knew just how much she loved that board, how overjoyed she was when SkySteps gave it to her. Now, it's nothing more than a pile of plastic.
"A-and they hit me with it every time I came up to breathe... I swam under them, but one of them came after me and p-pulled me by my wing up to the surface. I-i couldn't get away, somepony else grabbed my wing as well a-and the fins of my board hit my wing. I think it's broken..." her voice rose to a wail at the send of her sentence, tears streaming out of her eyes as her whole body trembled. 
"Shorty..." he whispered, feeling his blood burn and his whole body fill with rage. His magic seemed to bubble to the surface of his very being. If he ever found- no. He was going to find those ponies. He was going to break their boards, their wings, their horn. Make them watch as he burned down everything they ever cared about. He felt himself burn with hatred, but it all seemed to wash away when he felt her trembling grow stronger, shivering from the cold and the fear.
"I wanna go home" she cried, leaning on him in an effort to get up.
"I know, I know... Come on, let's go. I'll get you a new board, don't worry I'll take care of everything" he soothed, only gaining a small nod from her.
I'll make sure they pay

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Whoo boy. This was a big piece.
Got a few requests to see more on their relationship, with Tsundere Comet. Was going to be a cute thing, but turned out to be this.
Despite what he says, he'll never hurt her intentionally, he protects his friend no matter what. Poor baby, you have no idea what I'm planning.

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