This is a little Cas/Reader one shot based off of the imagine: Imagine Cas finding out that Sam and Dean killed his soulmate: you. Please let me know what you think! Feedback really helps.
"Please! I don't know what you're talking about!" you screamed for what felt like the millionth time. The ropes around your wrists were just as tight as they were hours ago, and the fear factor of being held captive by two six foot giants was still pulsing through your blood. The taller one came closer to you and barked, "You know exactly what I'm talking about. You're a werewolf!"
In the midst of sobs, you attempted to explain, "Wh-why would I be a werewolf? Th-they don't even exist. Please they're not real. P-please just let me go! I won't p-press charges I promise. Just let me go."
The tall one scoffed as the shorter one pushed him back. He shoved his face close to yours and the stench of whiskey from his breath attacked your senses.
"Oh sweetheart pressing charges should be the last thing on your mind, because you're not making it out of here alive." he growled. An involuntary whimper escaped your lips as a silver blade slid out from his sleeve. "Now we're gonna try this one last time. If you're not a werewolf, how do you explain this bite mark on your neck?" he demanded.
"I-I dont know!" you shrieked. "I really don't know! Oh God help me!" you pleaded.
The short one smirked again. "Oh God can't help you. No one can." Without another word, the swung the blade and it sliced clean through your stomach.
Castiel's head shot up as he heard screaming. He looked around frantically, trying to find out what was happening, but quickly realized that everyone was fine. No one else had heard even noticed. The voice kept ringing in his head. It was the voice of a woman, someone who was truly in pain. Why had he heard it? Cas stood in the abandon street of New York City with a sinking feeling in his gut. Something wasn't right. He felt as if someone had reached into him and torn something out. He couldn't place his finger on it, but some instinct was trying to tell him what to do, where to go, and before he could even think it through, his brain jumped on it. Seconds later, he was standing in the dungeon of the bunker, facing the backs of the Winchesters. In front of them, a girl, bleeding from her abdomen, mouth still hanging open from the scream. A deep sense of dread filled Cas as he precariously made his way to her. Dean spun around at hearing footsteps and was surprised at seeing the angel.
Before he could express his shock, Cas grumbled, "Dean step aside."
"Cas hold on a second-"
"NOW." Castiel said in a steely voice. Dean obeyed quietly, letting him advance. Cas approached you slowly, watching in horror as your soul rapidly faded. Silently he undid the ropes holding you down, and helped you into his lap. Your eyes struggled to focus on the figure in front of you, but something in your head was urging you to. The moment his hand had touched your skin something had just felt…right. When your eyes slowly focused, you saw a handsome man with brilliant blue eyes and messy hair, but beyond the hair was-you gasped.
"Shh. It's ok. It's going to be ok," the man soothed.
"I-I can" you struggled.
"Don't talk," he ordered.
"No, I - your wings," you spat out.
Castiel's eyes widened as you mentioned his wings. "Y-You can see my wings?" he cried.
You nodded and whispered, "They're beautiful." A wave of exhaustion washed over you, stealing all the warmth from your body. Your eyes began to feel like lead, and very slowly, along with your muscles finally going limp, they began to flutter shut.
"What? No. No no no. Not yet. Please. Stay with me. I-I can heal you. I ju-just need time. Please," Cas sputtered. He watched in horror as your soul reduced to barely a flicker, and finally, went out.
"NO!" Cas screamed in anguish. He buried his face in the crook of your neck and let out a heart wrenching sob. His whole body shook as his cries echoed in the dungeon.
A hand rested on his shoulder as Dean said softly, "Cas, buddy-"
Castiel spun around and slammed Dean against the wall. His crying had been replaced with unimaginable anger.
"Don't "buddy" me Dean. You killed her you son of a bitch," he hissed.
"Woah Cas cool it. I was just doing my job ok? She was a werewolf," Dean said.
"no, she wasn't Dean," Sam said in a voice barely above a whisper. Dean turned his head and looked at his brother beyond Cas's head.
"Say again Sam?"
"She…she saw Cas's wings," Sam said hopelessly.
"Yeah, so?" Dean questioned.
"So, Dean, only an angels soulmate can see its wings. And you. just. killed. mine." Cas said in a terrifyingly quiet voice.
Dean's face paled as the severity of the situation dawned on him.
"Cas we're so sorry-" Sam began. Castiel released Dean from his death grip and whipped around to face Sam.
"It doesn't matter!" he cried. Cas cried as grief washed over him again. He sunk to his knees and let out a deafening wail. Cas crawled to your body and took you into his arms as he cradled you back and forth, weeping shamelessly.
"It doesn't matter if you're sorry Sam, alright? She's gone," Cas cried, voice shaking violently.
"She's gone. My Eve is gone."