(This is a Soulmate AU, obviously!)

"Eyes open, Y/N. We don't know if Lucifer is using the same vessel," Sam warned, prompting you to roll your eyes. You knew that already. You hated when you brothers talked to you like you didn't know what you were doing. You were raised the exact same way they were even if you'd never met the fallen angel before. Still, you held your tongue and followed after them, as always.

You entered the room behind Sam and Dean, trying desperately to focus on your mission instead of the crowd all around the place. Your eyes went to the rock star in the middle of the room. "That's him," you said suddenly. Your brothers looked at you in surprise and Dean asked how you knew. You didn't know how to explain it. There was something that just told you it was him.

"I don't know. I can just tell. It's him, Dean." You caught Castiel's gaze to see him looking at you in confusion. "What?" He didn't reply. You looked back at Lucifer's vessel to find him already staring at you. Before you could say anything, he bolted. You and your brothers chased after him, but knew it was useless. He was the Devil after all. This was going to take a lot longer than you thought.

*time skip*

You spent weeks chasing after Lucifer. You lost track of how many different vessels he used. It wasn't until he somehow found his way back to his original vessel, Nick, that you were able to catch him. Nick was clearly the only vessel besides Sam that could contain him for long. When Sam and Dean brought him in, you were surprised at how easy a time they had and you wondered if he wanted to be caught.

You entered the dungeon of the bunker and came face-to-face with Lucifer. Your eyes met and he scoffed. "So it's true. I finally meet my soulmate and it's a Winchester. Dad has a sick sense of humor." You stared at him, arms dropping to your sides. You heard something fall to the concrete floor of the dungeon, but you couldn't pull your eyes away from Lucifer to see what had happened.

"Your what?" you asked in a small voice. Never before had you felt so out of control or scared. "His soulmate," Castiel's voice came from behind you. "Bull. She is not that monster's soulmate!" Dean growled out. Castiel took a step up next to you and put his hand on your shoulder. You were finally able to look away from Lucifer to meet Castiel's eyes.

"How did you know it was Lucifer when we saw him the first time?" Your brows furrowed as you thought back to it. "I don't know. I looked at him and saw his-his aura I guess or maybe it was shadow of his wings. I don't know!" Castiel gave you a small smile. "It's alright, Y/N," he told you before turning to your brothers and continuing, "She is his soulmate. She saw who he was through his vessel when no one else could. Only a soulmate can do that when we don't want humans to know what we are."

Your brothers started arguing and you were suddenly being pushed behind Dean. You nearly shrank back when you saw Lucifer's eyes glow. "Get your hands off her!" You flinched at his volume. "She's our sister. You won't have anything to do with her," Sam threatened. The tension in the room was high with your brothers protecting you and Castiel stepping in between you all and Lucifer.

"I think we all need to calm down," you offered softly. Your brothers looked at you with irritation written all over their faces. "It's not up to you," you whispered. You glanced back at Lucifer to see that, while he still looked furious at the fact that Sam and Dean, his eyes were no longer glowing and he had calmed a little.

"I need to talk to him," you said a little more loudly. Once again, Sam and Dean began to argue. "No freakin' way. I'm not leaving you alone with him," Dean growled. You put your hand on his shoulder. "De, he's not going to hurt me. He's chained up. And...if I am really his soulmate, I don't think he'd hurt me anyway. So, please. Just let me talk to him. Alone." Dean opened his mouth, but Castiel placed a hand on his other arm. "She's correct, Dean. Lucifer won't hurt her and they need to talk about this."

Dean wasn't happy about it, but he agreed. After dropping a kiss to your forehead and whispering for you to be careful, Sam lead Dean and Castiel out of the dungeon. That left you alone with Lucifer.

"What do you want? Now that you know, what do you want?" was the first thing you asked. Lucifer looked confused, almost like he didn't know what to say. "You know, I actually don't know. I had this plan. Big plans and now I can't," he said with a chuckle, "I guess that's what Dad had planned for me all along. One of his 'mysterious' plans."

"And what do you expect me to do with this? My brothers and I have been chasing you for weeks now. You've been creating chaos. We should put you back in the cage and throw away the key. That's what I want to do. That's what my brothers want to do. But I can't ignore the fact that you're my soulmate. So what do we do? I won't stop hunting and I can't trust that you're going to suddenly become a good guy. So where does that leave us, Lucifer?"

Lucifer closed his eyes, clearly enjoying the way his name dripped off your tongue. "LUCIFER! FOCUS!" He opened his eyes to meet your gaze again. "I don't know, Y/N. It's been so long. I don't think I can change." You let out a sigh and nodded. "I thought you might say that. I-I can't be with you like this. I never know what's going to happen with you. I'm scared," you admitted.

"I can protect you." You let out a scoff. "I'm sure you could. But who's going to protect me from you when you go off the rails and try to end the world again?" He didn't say anything and you nodded. "I can't do this. Soulmate or not, I can't handle this. I'm sorry." With that, you turned to leave the room. You looked back at him as you closed the door, you saw his eyes glowing again. You could practically feel his rage building. It was enough to feel stifling.

As the door closed, cutting your sight of him off, you felt tears pricking your eyes. "You okay?" Sam asked and you shook your head. "Why? Don't we already have crap luck in love? Why did it have to be me?" you sniffled. You let your brothers wrap their arms around you and they asked what they could do. "Just get him out of here. I don't want to see him." You pulled away and walked to your room, not knowing that Lucifer could feel every step you took away from him and that he was, in that moment, hatching a new plan.