(Flashback to a younger, human Sophia, around age 16. Her mother has taken her into the wilderness to teach her about hunting with nothing. They are sitting around a fire at night.)
Monica: Do you understand why I separated you and Castiel?
Sophia: Because you don't trust angels.
Monica: Well, yes. But that's not the whole reason, Sophia. I have to explain this to you, and you're still so young, you might not take it well. But you have 8 years before you need to make a decision, so you have time to think on this.
Sophia: Mom, what is it?
Monica: I separated you from Castiel to see how you would do when losing someone you love. Yes, Sophia, I know how much you love him even now. There is nothing you can do that I can't see. It's our blood. When you were born, I went to Aunt Mara.
Sophia: Why? She's never been right.
Monica: On the contrary, Sophia, she's never been wrong… about you. Aunt Mara has predicted your entire life so far. When it comes to you, she has been 100% accurate. She warned me you would be willful and rebellious. She told me you would be more powerful than all of us. After all, your father's line and my line are the most powerful in the world, and creating a child from those two? You were bound to be everything you are, Sophia. You can work magic towards us. Your father couldn't. I can't. I can't put a spell on you at all, but you can kill me with one.
Sophia: I would never-
Monica: I know, Sophia. But you CAN. No one else can. But none of this is the hard part of the decision you have to make. You will inherit everything from me- the house, the money, the businesses, my leadership position. The house, money, and the restaurant are things I am sure you understand. My leadership position, however? That is what I must explain to you.
Sophia: Explain?
Monica: Sometime in the future, and this may never happen, a great darkness may be unleashed. Remember the stories we used to tell you as a child about Amara, the Darkness?
Sophia: Of course. They gave me nightmares.
Monica: The Darkness is real, Sophia. They are not just stories. In our world, in our universe, God is the light. We don't worship God, but he does exist, and he is representative to us of Light. The Darkness is God's sister, whom we have always called Amara.
Sophia: Amara is real?
Monica: I'm sorry, Sophia. But this is the ugly side of what we are. She is our origins.
Sophia: What does this have to do with me?
Monica: Amara made us on a dare, to spite God. She created us to do her bidding, to show God that she was capable. She and Cain were lovers, Sophia. Cain was the one who figured out how to contain her in the Mark. He killed his brother out of jealousy, Sophia. They were in competition for Amara. It's why it's called the Mark of Cain. Even as just a mark, the Darkness was still powerful. She turned Cain into a demon from the inside out, all out of revenge. If he ever dies, truly dies, her power reverts back to us, to our leader.
(Sophia is silent, realizing what this means for her.)
Sophia: And what happens to me if any of this happens?
Monica: Cain can only be killed by his own blade. If someone were able to use it, they'd have to be bearing the Mark of Cain. If that mark is ever removed… Amara will be free. She is our Dark Mother, and we are the only ones who can kill her. You. If you choose this path, if you decide to succeed me as a leader, you may have to die to save the world from Amara.
(Sophia is quiet.)
Sophia: And if I choose immortality, I choose to become your successor?
Monica: If you want to inherit everything I have, Sophia. It's all or nothing. Those are the laws. But remember, you can choose not to inherit. I can choose another successor. You will become immortal either way, if you want to.
Sophia: And this is what you chose as well?
Monica: Yes. Because I would die for our people, Sophia. I would die for you. I know I'm not incredibly emotional or nurturing, but you are my daughter, and I would do anything for you. If there was a way to teach you to hunt and to sacrifice without having to ever hurt you, I would. But this is the only way.
Sophia: You killed Castiel to show me loss. To prepare me for the future?
Monica: If you choose this, Sophia, there is an 85% chance you will lose everything and everyone you love, even me. Even if Amara is never freed. But Aunt Mara says it will be so.
Sophia: What else did Aunt Mara say?
Monica: She said you will be a fierce and powerful leader, and you will be loved. She said you will be the first witch to walk through Hell, Heaven, Earth, and Purgatory, and live through all of them. Monsters will fear you, and humans will adore you.
Sophia: That doesn't sound so awful.
Monica: She did say something else, Sophia. She said you will love endlessly and powerfully.
Sophia: Did she know his name?
Monica: Names. Their names. She said there were three men. Two were clear, but the third, whom she said would be eternal, was murky.
Sophia: Will I have children?
Monica: No. One of these men will be chosen to succeed you. She did not know which, because you haven't decided yet.
Sophia: So, if Amara is freed, and I sacrifice myself, these men I love… they'll live?
Monica: Yes. Your blood can kill Amara. Your bloodshed.
(Sophia is silent for a moment. She seems to be struggling.)
Sophia: Can I make this decision now?
Monica: You can change your mind up until you are 24. Once you are 24, and you are ready to become immortal, I have to tailor the ritual to what you've decided.
Sophia: I've decided. I want to be your successor. If I have to die so that the men I love in the future live, then so be it. It will be what I can do to protect people I love.
Monica: Then I can begin training you.
(Sophia, age 17, visits her Aunt Mara. Mara smiles to see her.)
Mara: Sophia, how pleasant to see you. I had a feeling you were coming.
Sophia: Aunt Mara. I had to know if what you told my mother was true. I need to hear it for myself.
Mara: It is, Sophia. Castiel may be dead, but you will love three more men as much as you loved him, maybe even more.
Sophia: How did you know that that was what I was most interested in?
Mara: I'm your personal psychic, Sophia. I know where your mind is. What would you like to know?
Sophia: These men- who are they?
Mara: You will be immortal; they will be humans. Well, two of them will be. They will all be tall men, and very handsome. They will know how to fight demons and will have been raised as hunters. They will be brothers. You'll meet their father first. He won't know what you are, but you'll tell him. Trust him.
Sophia: And I'll fall in love with both of them?
Mara: Yes. The first one, the older brother, will end in tears, and the other may never end. It depends upon your decisions, Sophia. But I do know that you will love this brother for years before you are finally together. Your third lover will be present during this time as well. The time I'm speaking of is when your future becomes murky. Just know that there is no right or wrong during this time, Sophia.
Sophia: Why does it become murky?
Mara: I think because there are decisions you haven't made yet.
Sophia: Do you know the names of the brothers?
Mara: Yes. Winchester. Sam and Dean Winchester. You'll know which is which by the feeling in your stomach when you look at Dean. Sam is the taller and younger one.
Sophia: What about Number 3? He's a mystery man?
Mara: I'm not feeling anything about him, Sophia. I'm sorry. I wish I could help, because the feeling I get is that he's the most important of the three. What I can tell you is that you will love him before the other two- and long after the other two are gone. He will also hurt you the most, though he will love you beyond all measure. There is nothing in this Universe that this man would put in front of you, but he will do a lot of damage to you and the world around you. I get the feeling like events will get in the way, but when it's your choice… you two will always choose each other.
Sophia: Well, I guess that's comforting. Will I love them as much as I loved Castiel?
Mara: This mystery man, Sophia… You will love him more than you've ever loved anyone. I wish I could tell you more.
Sophia: I'll come back when the time is right.
(Silently, Sophia hugs her aunt and leaves. Castiel comes out of the back room.)
Castiel: She didn't pick up on my presence?
Mara: I didn't like lying to her or her mother, Castiel. They both think you are dead.
Castiel: I understand, but she needs to make her decisions free from the thought of me. She needs to think that there's something bigger out there for her. Her people need her. I can soldier on without her until the time is right. If what you see is true, I'll be back for her someday.
("Pour Some Sugar On Me" blares over the speakers in the strip club. Dean, Sam, and Castiel try to blend in as a group at a table. Castiel seems to be uncomfortable until he sees Sophia, dressed in next to nothing besides an extreme push up bra, a pair of sexy underwear, and some stilettos. He is incredibly turned on by her, but is also outraged at the reaction of the mortal men around him. Both Sam and Castiel, even Dean, are mind blown at how incredibly hot and sexy she is, how she seems to have a talent for this, and also the reactions of the men around them. The entire room is throwing 20s in her direction. Men cheer for her as she dances, but it's clear she's not interested in the attention, or even the money. She has her eye on a demon in the corner. The four of them are looking for this demon and Sophia will not let him out of her sight. She makes her way over to where the three of them are seated. As she has been instructed by her "boss" at the strip club, she focuses on the most engaged customer-unsurprisingly, Dean. Castiel and Sam both glare at Dean as he enjoys the view.)
Dean: What?! I'm just enjoying the view.
Sam: Stop it, Dean!
Dean: I never said anything when you were drooling over her and I was dating her!
Castiel: Stop it. You'll blow our cover.
(Sophia climbs down and into Dean's lap, grinding on his groin hard. Dean slips a few 20s into her underwear, and Sam and Castiel look about ready to explode. Sophia leans in close to them.)
Sophia: I'd get a move on if I were you guys. That demon's looking to bounce soon.
Castiel: We'll need a diversion to follow him.
Sophia: I'll give you one.
(Sophia stands up straight again, and men cheer her on again. Castiel is in disbelief.)
Sam: No matter how many times I watch guys turn their heads to check Sophia out, it still annoys the crap out of me.
Castiel: It's horrifying to watch how these men defile her with their eyes.
(Sam looks at him, clinking beer bottles with him.)
Sam: Amen, Cas. Amen. To respecting Sophia.
(Sophia lets men slip bills into her underwear as she makes her way over to dance on the bar. She finds a bottle of the most flammable liquor, pouring it on the bar. Men cheer as she pours a little down her throat. She lights a match, setting the bar on fire. Men cheer and no one seems to be upset, not even her "boss". Sophia nods her head towards the demon, and the guys move on it. They follow the demon to the back, where they grab him and lock him into his body with handcuffs. Sophia puts the fire on the bar out with a hand, using the water from the bar as well. Hundreds of bills in her underwear and bra, she heads backstage again, throwing on a pair of yoga pants and a zip up hoodie. She switches shoes and heads around to the back of the club to find the guys. She finds them loading the demon into the trunk of the Impala. She jumps into the back with Castiel, and they all drive off.)
(Back at the bunker, Sam and Dean take the demon to the dungeon to chain him up. Castiel eyes her hoodie, unzipped to her cleavage, and her hair swept up messily. He rubs her cheek with his hand.)
Castiel: Did any of those men touch you?
Sophia: No.
Castiel: Dean seemed to enjoy your show…
Sophia: The guy who was my boss instructed me to engage the most focused customer, Castiel. You and Sam were busy glaring down any guy that paid attention to me. Dean couldn't take his eyes off me, so I had to engage him. That's all it was. I wanted it to be you, but you never even looked at me.
Castiel: I was just uncomfortable with what those men were all thinking.
Sophia: What were they thinking?
Castiel: Things we've only done to each other at our most uninhibited. I enjoyed watching you, but I would have enjoyed it much more in private.
(Castiel, feeling protective, kisses her and puts his arms tightly around her. He holds her tight, running a hand through her hair gently. They are still kissing when Dean and Sam come upstairs, heading to the kitchen for beers. They hand one to Sophia and Castiel.)
Sam: Figured you'd probably need one after your undercover assignment.
Sophia: Be glad to never strip again.
Dean: You know, if you were ever strapped for cash, you could do it professionally.
Sophia: I think I'm comfortable NEVER doing it again.
(Sophia has been losing control of her power ever since the Darkness was released, and Castiel has discovered why. He is confronting her.)
Castiel: Sophia. Were you ever going to tell me?
Sophia: I'm sorry, Castiel. This was in motion for a long time. I can't derail the train now.
Castiel: I refuse to accept that this is where our story ends.
Sophia: It may, it may not. All I know is, this is something that is going to happen. I have to make the ultimate sacrifice, even if it means losing everything I love.
(Castiel grips Sophia tight, sliding a hand to her cheek.)
Castiel: Sophia, this is something we need to fight. I'll do everything I can to save you. I'll stop at nothing.
Sophia: Won't do us any good to lose you, too, Castiel. Just let me do this. I signed up for it. Dean and Sam can't defeat Amara. I can.
Castiel: Sophia!
(Sophia kisses Castiel forcefully to silence him. She is emotional and her eyes are purple.)
Sophia: Please, Castiel… This isn't something we can change. If I kill her, you, Sam and Dean will survive. That's all I need.
Castiel: Sophia, please…
(Sophia lightly puts her fingers over Castiel's lips.)
Sophia: Let me protect you. I've known about this for decades, Castiel. I've accepted it. I CHOSE it. This is what I chose this life for.
Castiel: What do you mean?
Sophia: My aunt predicted all of this years ago. She told me I would love three men. All three of those men are here. I always knew it was you, Castiel. It was always going to be you, baby. I got some abilities that I never told anyone about, not even my mother. I didn't tell anyone, but I inherited the sight from my Aunt Mara, and I knew even then- you would be back. I didn't know how, because I was certain my mother had killed you. But I just KNEW, you were my mystery man. My aunt Mara didn't even know it. And if I was wrong, I didn't want to live without you. I figured I could go out doing some good.
Castiel: She did know.
Sophia: What?
Castiel: I told her to lie to you. I'm sorry, Sophia. But I told her to lie to you and Monica. She hated it, she did. But I wanted you to make your decisions free from the thought of me. No one could have imagined you'd choose this. But you know me, Sophia; when it comes to you, I've always been selfish. I don't want to lose you.
Sophia: Castiel, it's only a 50/50 chance.
Castiel: That's 50% too much. Sophia.
Sophia: What's done is done, Castiel. I made my choice long ago and I'm not changing my mind. I can't now.
Castiel: I won't stop fighting for you, darling. I love you.
Sophia: You know; you could honestly have cared less the past few years. Now that there's a chance you'll lose me, you're willing to go to drastic measures and fight for me?
Castiel: It's not like that, Sophia. I would fight for you any day if I thought you needed the help. I've always come when you called… except when I couldn't. I've always loved you, Sophia. I never stopped.
Sophia: Right. I guess Purgatory was me not needing your help.
(Sophia walks away, ending the conversation. After a few seconds of trying to follow her, Castiel realizes she has rooted him to where he stands, and he cannot follow her.)
(Sophia lets herself into an apartment, barely furnished. She lets the door slam behind her, and hears a rustling from within. Casifer comes out from the back, smiling at the sight of her.)
Sophia: I can't lie, Luci, I like you in this meat.
Lucifer: Poor Jimmy Novak, having an angel AND an archangel inside him. How'd you like both of us inside you, too, missy?
Sophia: I thought you'd never ask.
Lucifer: Sing me a little song, witch.
Sophia: Baby, drop them bones, baby, sell that soul, Heaven fare thee well, somebody gotta, gotta raise a little Hell.
(Casifer slams her against the wall, ripping off her clothes. She rips his off, and they have sex pressed against the wall. Casifer laughs.)
Casifer: You're a real wildcat, Blackwood. I don't think Hell would ever be ready for you.
Sophia: Yeah, well. I hope Amara is ready for this duo to murder her the way you just murdered this.
Casifer: Your skin doesn't seem to be crawling.
Sophia: It's easier that you're in Castiel's skin.
Casifer: How long did it take you to figure out it was me in here?
Sophia: I just knew.
(Casifer appears, but Sophia has no idea that Lucifer resides within Castiel's vessel along with him. Lucifer has put up a block to shield her from the knowledge that he dwells within Castiel. He takes her hand, and she jumps into his arms, kissing him.)
Casifer: It's been too long, Sophia.
Sophia: You're right. It's been four hours.
(Casifer hides his shock at the frequency the two have sex as she strips him naked, climbing on top of him. It's hot, passionate, and Lucifer can barely handle himself with her. She pins him down, his hands clumsily running over her body.)
Casifer: I can barely keep up.
Sophia: Is something wrong?
(Lucifer catches himself, slipping back into the Cas mask.)
Casifer: I'm fine. Come here.
(Before she can respond, he kisses her, and she lays a hand on his chest gently. As their sex continues, she leans her hand on him a little more heavily, and trying to read his heart. His comment raised a flag for her. Casifer feels a pull at his heart, and doesn't realize that Sophia is actually reading Castiel's heart, which has always been clear to her. She leans back.)
Sophia: That's strange.
Casifer: What?
Sophia: You usually don't have a problem keeping up with me. It's usually the other way around. I can't read your heart, Castiel.
(Casifer is fumbling for a response.)
Casifer: Well-
Sophia: And you should have known that that's what I was doing when I touched your chest.
(They both freeze, and Sophia slams her hand around Casifer's neck.)
Casifer: Please don't-
Sophia: Who are you?! Where is Castiel?!
(Casifer throws her off of him, pulling up his pants and trying to gather himself together quickly. Sophia stands there in her underwear and bra, glaring Casifer down. Her knife is in her hands, and she is ready at any moment.)
Casifer: He's still in here, Sophia. You kill me, you kill him, too.
Sophia: Who are you?!
Casifer: Castiel and I are brothers. He gave me permission, Sophia.
Sophia: He neglected to mention it to me.
Casifer: It was a spur of the moment decision.
(Sophia is quiet, reaching out with her power and trying to read whoever is in Castiel.)
Sophia: I can sense something dark about you. You're no brother of Castiel's. Who are you?!
(Casifer is quiet for a moment, considering her. Here she is, standing in her bra and underwear, ready to stab him, and yet he can't bring himself to hurt her. Is it Castiel's influence holding him back? Or does he actually feel for her?)
Sophia: Well?!
Casifer: I've seen you through his eyes now. I've seen him through YOUR eyes, too. You remember, don't you, Sophia? You and I did a little bump and grind that no one could have expected.
(The look on Sophia's face is horror and shock. Then, she looks as if she is about to be sick.)
Sophia: Lucifer?! He said yes to you?!
Casifer: Desperate times, beautiful. Your Cas was aching to be of use. He's been feeling benched, been feeling like a liability. He thinks he's useless to protect you against what he has yet to accept is your horrendous fate.
(At that, Sophia cannot control her tears welling up. Her eyes flip to purple. She lowers her knife, knowing Lucifer poses no threat to her. She pulls on her pants, then her boots. Her hands are shaking, and she looks at Lucifer with puppy eyes.)
Sophia: Not useless. He's not a liability, he'll never be a liability. Not to me. Not to us. He's a warrior like us. He's one of us. He can't save me; I can't even save me.
Casifer: Well, now he's new and improved, and when he finally does expel me, he'll have some new tricks to play with as a token of my appreciation. Let's save this sad world together, Sophia. You and me. Come on, what do you say?
(Sophia looks at him intently. Then, she smiles a little bit.)
(Sophia lets herself into an apartment, barely furnished. She lets the door slam behind her, and hears a rustling from within. Casifer comes out from the back, smiling at the sight of her.)
Sophia: I can't lie, Luci, I like you in this meat.
Lucifer: Poor Jimmy Novak, having an angel AND an archangel inside him. How'd you like both of us inside you, too, missy?
Sophia: I thought you'd never ask.
Lucifer: Sing me a little song, witch.
(Casifer slams her against the wall, ripping off her clothes. She turns on an iPod plugged into speakers, blaring Dorothy's "Raise Hell". She rips his clothes off, and they have sex pressed against the wall. Casifer laughs.)
Sophia: Is this the best you got?
Casifer: You're a real wildcat, Blackwood. I don't think Hell would ever be ready for you.
Sophia: Yeah, well. I hope Amara is ready for this duo to murder her the way you just murdered this.
Casifer: Your skin doesn't seem to be crawling.
Sophia: It's easier that you're in Castiel's skin.
Casifer: How long did it take you to figure out it was me in here?
Sophia: I just knew. You know. You were there.
(Castiel is revealed to have said yes to Lucifer, who is now in his body. Sophia's eyes begin to glitter, and she smiles macabrely.)
Sophia: Maybe this Castiel will finally get to enjoy a few things.
(Sam and Dean are horrified as Sophia seems to flip a switch inside her that embraces the darkness within her. Castiel/Lucifer leans in, kissing her, reaching around to give her ass a slap. He squeezes, and she laughs.)
Castiel/Lucifer: Ready to go dance with devil, darlin'?
Sophia(in a singing voice): Baby drop them bones, baby sell that soul, Heaven fare thee well, somebody gotta, gotta raise a little hell…
(Castiel/Lucifer throws an arm around her, and as they walk by Dean, she slips something into his hand and winks. Dean looks down at it after they leave. In a small envelope, there is a moon shaped pendant and a short note: Journal. My room.)
(Sophia is in the apartment again, to see Casifer. He enters from the back of the apartment. She's angry.)
Sophia: You tried to kill Sam. I told you Sam wasn't part of any deal. You weren't to hurt him, Lucifer.
Lucifer: I wouldn't have killed him.
Sophia: No, just eviscerated him!
(Sophia slams Casifer against the wall, her hand tightened on his neck. She can see Cas below the surface, struggling to get out.)
Lucifer: Well, he's still alive, so calm down. Don't damage this fine packaging, Sophia.
Sophia: You know, it occurred to me, Luci. Besides Amara coming for you, you really had no reason to escape the Cage. You could have fought her from within the Cage and still won. It led me to think about it. You reached out to Sam, posing as God. We're valuable to you. You need us. You care about us. Or maybe… just one of us.
Lucifer: I don't care about any of you.
Sophia: And even though you've said you're going to kill us, you've yet to truly try and kill any of us. I mean, you could kill Castiel right now and keep his meat suit. But you haven't. So maybe it's that Lucifer isn't that much of an Antichrist after all…
Lucifer: Shut it, Sophia.
Sophia: And then I thought, maybe it's Sam. I could understand. He's pretty hot, kind of a monster in the sack, puppy dog eyes for days, not to mention, built like a Greek god. He'd be my choice in that sense. But then I realized, there has to be something in it for you. Sam will never let you inside him ever again, ever. So I scratched him off my list.
(Lucifer fights her, but not with any real aggression, just to stop her from talking. He doesn't want her to force him to confront the truth. She reinforces her grip on him, smiling.)
Sophia: I ruled out Dean instantly. He's useless against Amara, since every time she's around, he can't hurt her. Sure, he can talk a pretty big game about how he wants her dead, but she just won't let him slam a knife into her. He may be out of this world gorgeous, especially those fanfiction green eyes!, but you have nothing to gain from him. So then, who does that leave out of Team Free Will? Castiel and me. I could see you caring for Castiel- he's your brother, after all. I can feel you two tussling in there, just like brothers. Lay off the noogies. But you know, these days, I'm the only one who seems to think Castiel's worth something. Everyone thinks Castiel is an angel killer, or expendable, or that he's not a hero. If the world could see that hot little angel through my eyes, they'd recognize him as their new god and erect temples and monuments to him and start worshipping Castianity as the new world religion. So yeah, I could see it being Castiel that you did this for. But then I realized-
(Lucifer uses all his strength to shove her all the way back against the wall across the room. He chokes her, but she snaps his wrist. She kicks him down onto the couch, using her foot to hold him in place by the crotch. He freezes, his eyes pleading with her to stop.)
Casifer: Sophia. Please.
Sophia: It's me. I'm the only one you can't beat. That sounds terrible, but it's true. No one has ever beat me. And you knew how to get to me- come for who I love. You must have thought you hit the jackpot when Castiel said yes, didn't you? It's even better than Sam, really.
(Lucifer looks defeated. He gently takes her ankle, and she allows him to lower her foot. He stands, his eyes lowered in defeat.)
Casifer: Do you know how hard it is to see you through Sam's eyes, how he's always seen you, and then how Castiel sees you, and not love you?
(Sophia's smile freezes on her face. She is shocked.)
Sophia: Oh, my God. You really are. I was so hoping you'd tell me it was just a joke.
Casifer: No point in lying. The second I got into Sam's body and saw you through his eyes, I had to have you. And now Castiel! His love for you is so pure. It's like a drug, Sophia. I can see why he rebelled every single time- I would have, too. It's like heroin. He really loves you. I know you don't think he cares about you, but he put himself through this, he said yes to me, all for you! The way he feels about you, it's addicting. I can feel it constantly. The way they love you… It would make anyone, even me, love you… and I can't make it stop. It's been years since I was inside Sam, and I haven't been able to stop it since. So I will stop Amara for you, Sophia, not for myself. Because one day, I want you to look at me with even a fraction of what you look at Castiel with. You look at his meat suit that way even now, though you know it's not just him in there.
Sophia: I still can't believe this is true.
Casifer: Believe me, I can't either. I thought my days of being in love were long gone, especially lusting after someone else's girl.