Febuwhump Day Seven: Used as an Experiment. After a witch tries an experimental new spell on Sam, he is left in agony and asks Dean to kill him.

Title: Shaking

! Major Character Death ! Hurt No Comfort !

Sam writhed and screamed uncontrollably on the cot. Dean pressed his shoulders down to keep him from falling off the mattress.

"Dean!" Sam cried.

"Sammy, I'm right here," tears stung at Dean's eyes.

Sam screamed and his back arched up and his head thrust backwards. His hands flew out to the side and hit Dean in the leg. "Can you hear me?" Dean asked.

Sam panted. His eyes were wide open, but his gaze was empty. This should have never happened. If Dean hadn't suggested they split up, Sam wouldn't have been abducted by the witch. She tied him up and injected angel blood into his veins, her early attempt at a homebrew spell to peek through the veil and locate the gate to heaven.

"You're in the bunker. You're safe. I've got you."
Sam shrieked. Dean looked desperately at Cas. "You've got to do something," he pleaded, but he already knew the answer.

"I'm sorry, Dean. I can't heal a spell."

Dean shook his head and turned back to Sam. Blood dripped from his nostrils down his face. "Please," Dean whispered, "Stay with me."

"D-Dean," Sam gasped, "I can't- I'm dying."

"Shh, no, you're gonna be fine. You're alright."

"No," he shot a hand forward and latched onto Dean's shirt, pulling him close, "You've done everything for me. I would have been lost without you."

"Sam, please-" tears trickled down Dean's cheeks.

"I love you- AH," he shrieked and his body jerked wildly, losing his grip on Dean's shirt. Dean's heart ached in his chest, seeing Sam like this and not being able to do anything. They'd called practically everyone they'd ever met, even uttered a prayer to God, but no one could help Sam.

"I need you to kill me," Sam croaked.

"I can't."

"P-please. I'm dying and it hurts so bad. I can't," Sam broke into convulsions, seizing and screeching in pain. Dean was being torn apart, his heart ripped in two. He couldn't watch Sam die again, he couldn't let his little brother go, not like this. Not after everything they'd been through.

"Cas, is he really dying?"

Cas looked somberly down at Dean. "He has a few hours left, at most."

"No. No, no," Dean shook his head.

"I can't do it, Dean. I need you to."

Sam stared blindly towards Dean. He was in agonizing pain, surrounded by pitch dark, and aware that he was dying. Dean knew the answer was clear, but he couldn't do it. He couldn't let Sam go. "Don't ask me that."

"It hurts," Sam whispered and there was a childlike vulnerability in it. He was begging his big brother to protect him one last time.

Dean gripped Sam's hand in his own. It was hot and wet with sweat. Sam squeezed back. "Okay," Dean breathed.

"Thank you."

Cas spoke from behind Dean, "I can-"

"No. It has to be me," Sam had always been his responsibility and he had asked Dean to do it. This was his only choice. "Sammy," Dean's voice broke. He brushed Sam's hair out of his face. "You're gonna be okay. I love you, little brother."

"I'm s-sorry," Sam forced out.

"No 'sorry's. You did good. I'm so proud of you," Dean's hand trembled as he pulled his gun from his waistband, "I couldn't have done anything without you. You know that right?"

Sam nodded jerkily. "It's not your fault."

But Dean didn't believe it. He would spend the rest of his life blaming himself for this moment.

"I want you to be happy. Don't try to bring me back."

Dean tried to speak, but the words didn't come out. He held the gun beside Sammy's head, an inch away so he wouldn't know the pistol was aimed at him. He wouldn't see it coming. Sam broke into violent cries again and Dean let out a sob. "I love you," he managed, and the shot rang through the bunker. Then it was silent. No more screams or pleas. No more scraping of the cot legs against the concrete floor as Sam convulsed.

The gun clattered to the floor and all Dean could do was watch the whole in Sam's head as blood drained from it. Cas moved to stand beside him and placed a hand on his shoulder, but Dean couldn't feel it. He couldn't feel anything. Sam was gone. This was never supposed to happen. Dean was meant to die first. He'd always planned it that way. He didn't know how to live without Sam. This was all wrong.

And the blood just continued to fall.