I was already in the Armory with Alaric, preparing to interrogate Sybil, who was still in her cell in the basement.

Stefan was also here, on the phone with Caroline. "Hey."

"Hey. For future reference, just because I spend the night with Bonnie doesn't mean you can't sleep in your own bed."

"Right, yeah, no. I--I crashed at the Armory. I figured I'd give you two some space. How's Bonnie doing?"

"Glued to Enzo's side, despite all the awful things he's saying to her. It's gonna take another day or two of starving him before she can get started with his humanity switch."

"Well, if anyone can bring him back, Bonnie can. Hey, you know what, I should probably get going. Kaylin and I have a little date with a siren."

"Be careful. You've seen what Sybil can do when she gets inside your head."

"As long as this tuning fork is ringing, she can't."

"Is there some sort of engaged person shorthand for, 'Good luck and... I'm with you in spirit'?"

"Yeah, I think it's 'I love you'."

"I love you, too."

Stefan hung up.

Alaric brought us coffee, setting it on the adjacent table.

I picked up a coffee. "Hey, thanks."

"Oh, thank the nanny," Alaric told us. "She's the unwitting enabler."

An intern of Alaric's named Georgie walked in. "Oh, hey."

"Uh, I thought I told you not to come in today," Alaric told her.

"Well, I heard there was a coffee shortage and came running," Georgie told us.

"Well, actually, we're in the middle of a major project," Alaric told her. "So why don't you take the day off?"

"Major project?" Georgie repeated. "Sounds sketchy. Got a girl tied up in the basement?" Alaric, Stefan and I exchanged a look. "Jokes. Okay, I'll leave you to it."

Georgie walked out, leaving the Armory.

Stefan and I turned to look at Alaric curiously.

"I can only deal with one temptress at a time," Alaric told us. "Anyway, any word from Damon?"

I sighed. "None. And that's what worries me."

********

Stefan and I went down to the basement cells to talk to Sybil.

I tapped the tuning fork against the glass, causing it to vibrate, ring and hurt Sybil. "The all-powerful Siren. Imprisoned by a fork."

"Says the girl who can be killed with a stick," Sybil replied.

"What is it about this thing that hurts you so much?" Stefan asked.

"And here I thought you had me all figured out," Sybil told us. "Guess not."

I rang the tuning fork again. "If this disrupts your psychic ability, then why is Damon still your puppet?"

"I tinkered with the deepest reaches of his subconscious," Sybil answered. "If Damon's still serving me, it's because deep down, he wants to."

"Why are you doing this to him?" Stefan asked.

"It's all Damon, Damon, Damon," Sybil told us. "Aren't you even a little curious about who I am?"

"No, actually," I answered. "All we care about is how to save our brother."

"Well, fortunately, the answer to your question is... a story," Sybil told us. "About me. You like stories, don't you?"

"I prefer nonfiction," Stefan told her.

"Well, then you'll love this one," Sybil told us. "A long time ago, in a little Mediterranean village, there was a girl. The fate of psychics was exile. Which is how our poor, innocent, forsaken village girl ended up on a raft... The current carrying her into the rocks of a cold and distant shore. But abandoned though she was meant to be, alone she was not. There she met the girl of the island. Exiled together, connected in psychic ability, two sisters in everything but blood, destined from that moment to one day become... the sirens. So you see, I understand why you would do anything for your brother. Because my sister will do anything for me."

"Will do?" I repeated. "Present tense?"

Sybil chuckled in amusement. "Oh, did I forget to mention there are two of us? Me in here. And her out there."

Stefan and I were both alarmed.

********

Stefan took the tuning fork from me, banging it again, making it ring.

Sybil gasped in pain. "Would you please stop doing that? It is complete overkill."

"What do you mean, two Sirens?" Stefan asked.

"I thought you were the smart Salvatore, Stefan," Sybil told him. "Every single mythological interpretation of who I am mentions Sirens. Plural."

"Well, those same myths also say that you should have the lower half of a bird," Stefan told her.

Sybil laughed. "Well, luckily for us all, you can't believe everything that you read."

"Enough," I told her in annoyance. "Who is she?"

"Patience, Kaylin," Sybil told me. "I promise you'll find out soon enough."

********

I used the tuning fork on Sybil again. "You're stalling. Who is the other Siren? Who's your sister?"

"You think hurting me is gonna speed this up?" Sybil asked. Stefan took the fork from me, stopping the vibrating from harming Sybil. I rolled my eyes in annoyance, impatiently crossing my arms over my chest. "Thank you. Now, despite enjoying each other's company, the girls had another constant companion... hunger. The one who had survived on the island this long had a plan." The plan was for the two girls to lure ships of sailors to the island. "But the girl of the island knew better. She had done this before, called out to passing sailors with her mind. But no matter how keen her psychic reach, the shoals around the island were sharper."

"So, you beached the ship," Stefan told her.

"Try annihilated," Sybil told us. "Dashed upon the rocks, dooming its sailors to death. But, silver lining. Their sweet, sweet provisions would soon wash up on shore. Kaylin, stop me if this sounds familiar. One good sibling, determined to live like a monk, and one selfishly evil sibling, willing to murder to satiate their hunger. Oh, come on, you get it. The parallels are too good. The village girl is like Stefan, and the island girl is like Damon. So, now here's the test, Kaylin. Which girl are you?"

I didn't answer, giving her an unimpressed glare.

********

Stefan looked at Sybil. "Look, we don't have to be enemies." I rolled my eyes. "Kaylin, Damon and I had nothing to do with the Armory until you possessed him. If we're enemies, it's because you chose this path. We didn't ask for any of this."

"God, you sound just like her," Sybil told him. "A victim to the last. She insisted the island would nourish them. And when it didn't, her faith was shaken. God did not provide. That was up to her sister. The other side of the island was the wild boars' domain. It was dangerous, but she knew she must hunt. And behold. God was good."

"Or maybe there were no boars on the island," Stefan told her. "You kept luring ships into the rocks. Killing for provisions."

"And do you want to know the sickest part of all?" Sybil asked. "There were no provisions on the ships. Only sailors. And so, an innocent girl became a monster. All because her older sibling forced her to adopt her lifestyle, even if it meant killing and eating men to stay alive. Kaylin, you were forced into this existence by Stefan because he asked Katherine Pierce to turn you, and Damon nearly turned you into a monster before, always trying to sway you to the dark side. You've resisted, but you had been so scared that you would turn back into the girl that you were in the '20s, the vicious killer that didn't care who she hurt. I ask you again, which girl are you? And you continue  to love the man that you were with during that time, even if both of you have changed for the better."

I got annoyed with her always trying to figure out who I was. "Here's all you need to know. Whatever Stefan, Damon and I have done to one another in the past, it has been forgiven. He is our brother, and there's nothing you can do that will ever change that."

Sybil chuckled. "I think you've overestimated your sibling. And clearly, I have underestimated mine."

Stefan and I were both shot with vervain darts that made us fall unconscious before we could see who shot us.

********

Stefan and I woke up on an island, confused, standing, looking around, trying to figure out how we got there.

Sybil walked closer. "Hey, sailors."

"What did you do t us?" I asked.

"You're in my head," Sybil told us. "I brought you here to show you my memories. Your silly fork stopped ringing. There's nowhere to run. So walk with me."

"Oh, so is this where you attack our psyches?" Stefan asked. "Try to break us down?"

"Normally, yes," Sybil answered. "But the boss has other plans for you two."

"The boss?" I repeated.

"Mm-hmm," Sybil answered.

"What are you talking about?" Stefan asked.

"He thinks you're worthy of hearing the whole story," Sybil told us. "Shall we continue?" She led Stefan and me into a cave. "For years, my sister and I lived as cannibals. One willingly, one blissfully ignorant. Until I discovered this. Where my sister had buried the sailors she had murdered. Only visible at low tide. It was the perfect hiding spot."

"You discovered?" Stefan repeated. "You're not the girl from the island, are you? You're the village girl."

Sybil looked upset. "I tried." Her voice began breaking. "I tried so hard to be good. My sister forced this existence on me."

"What, you expect us to have sympathy for you?" I asked in annoyance. "After everything you've done?"

"Maybe, maybe not," Sybil told me. "It all comes down to the same question. Which Siren is your spirit animal, Kaylin?"

********

Stefan, Sybil and I were still in the cave, talking over the skeletons on the ground.

"I couldn't believe it," Sybil told us. "All those years, my sister tricked me into eating human flesh. But I had to hear the truth from her mouth, so I confronted her. You should've seen the look on her face. Oh, wait, you will. Here she comes now."

Stefan and I turned around to see the other Siren walk in, recognizing her as the nanny that Alaric and Caroline hired to babysit Lizzie and Josie, in shock, horrified. "No."

"Stefan, Kaylin, you've met my sister," Sybil told us. "Seline."

********

Stefan and I turned to Sybil incredulously.

"Seline is the other Siren?" Stefan asked.

"What's more shocking?" Sybil asked. "That she secretly fed me human flesh? Or that she's now masquerading as a freaking nanny?"

"Let us out of here," I told her. "Now!"

"Why, so you can go warn Alaric?" Sybil asked. "You're assuming that I'm gonna let you remember this when you wake up. Sorry. Orders from above. Well, below."

Sybil grabbed both me and Stefan by the heads, erasing our memory so that we wouldn't remember, making us both groan in pain.

********

Stefan and I woke up in the basement of the Armory outside of Sybil's cell, standing, seeing that she was still inside, confused and suspicious.

"What did you do to us?" Stefan asked.

"You tell me," Sybil told us. "What do you remember?"

"You confronted your sister," Stefan told her. "She turned you into a cannibal against your wishes."

"And who exactly is my sister?" Sybil asked.

I tried to remember, but I couldn't. "I don't know."

Sybil gave us a look of fake sympathy. "How frustrating."

"Why are you still here?" Stefan asked. "We were out cold, you were in our heads. Why didn't you escape?"

"And leave you with such a dramatic cliffhanger?" Sybil asked. She chuckled. "I'm not that evil. I was about to answer your question. How you can save your brother." She looked at me. "But for the last time, I need to know, are you an island girl or a village girl?" I rolled my eyes, picking up the tuning fork, about to use it. "Wait. Answer me, Kaylin. This is important. Who are you in this story? The victim, who was turned into a vampire because of her brothers' infatuation with a vampire named Katherine Pierce? The victim that had her child beat out of her by her mother's lover, who was compelled time and again, both as human and vampire? Or the monster whose methods of destruction won over even Klaus Mikaelson in Chicago, who has a short temper but a big heart, and still loves him despite the fact she knows that it's wrong? Answer me. Who are you?"

"I'm both," I answered.

Sybil was surprised by the answer, impressed. "I was wrong about the two of you. You are worthy. You're ready for the truth. When I learned the truth about what my sister had done for me, I did the only thing a decent person could do. I threw myself off the cliffs. As I lay dying, I prayed. For mercy. For love. For forgiveness." She told us about how when Sybil was nearly dying, her sister called out to a man named Arcadius, and he saved them both by turning them into Sirens. "My sister... She made a deal with Cade. Immortality, beauty and youth, for the two of us... if only we served our new Lord and master. We feast on the flesh to keep us beautiful, and he collects the souls of the wicked. In Hell."

"Hell?" Stefan repeated. "As in, literal Hell? Come on. Just tell me the truth. Who's Cade? What is he?"

"He's the answer to all your problems, Stefan," Sybil told him. She looked between us. "You want to save your brother? All you have to do is kill the Devil."

Stefan and I were confused and skeptic.

********

We were still talking.

"I don't believe you," I told her.

"Which part?" Sybil asked. "We covered a lot of ground."

I sighed. "Hell. The Devil. None of it exists."

"Did you believe in vampires before one beat you until you lost your child and compelled you to forget, before you became one yourself?" Sybil asked. "That's the trouble with facts, Kaylin. They're true whether you believe in them or not. I promise you, just as my sister promised me. There was a man named Cade. The people he loved damned him. And only at the very end did he finally give up on them, only when the smell of his burning flesh was searing his nostrils, did he see them for what they really were. Monsters. Just like you and me. So, Cade damned them in return. With his last breath, he let loose a psychic blast so powerful that it created its own world. Call it Hell if you want. It doesn't matter what name you give it or whether you believe in it or not. Either way, that is where Cade feeds on the souls of the damned. It's where he waits for your family."

"Stop making this about us," I told her. "We're trying to help our brother."

"Oh, but this is about you, all of you," Sybil told us. "Stefan, did you really think all your pathetic attempts at atonement would save you from the fate that, deep down, you know you deserve? A fate befitting the glorious Ripper of Monterrey?"

Stefan shook his head. "No. That was almost 100 years ago. I'm not that person anymore."

"It doesn't matter, Stefan," Sybil told him. "That stain will always be on your soul, no matter how hard you try to wash it away." She looked at me. "Just like all of your deeds still stain your soul as well. So, stop fighting. It's easier that way."

"Maybe I do deserve it, but Damon and Kaylin don't, because I made them what they are," Stefan told her. "So, if it's my fault, damn me. Not them."

"Damon's fate is already sealed," Sybil told us. "I reached into his mind and gave him a look at what awaits him, and even that little spoonful was enough to make him flip his little humanity switch. He chose to serve Cade for all eternity, rather than experience another second in that kind of torment. Damon believes in Hell. And soon, both of you will, too. Because you're just as doomed as he is."

Stefan and I were both worried and skeptical, looking at each other, sighing.