The bunker looked as abandoned as it always did on the outside. I wasn't fully sure I believed Lucifer, although his logic was sound, I wanted confirmation.

So I took a deep breath, pushing the heavy metal door open without a sound. The Winchesters sat in the library, no sign of Castiel anywhere. I wasn't sure if I wanted to be relieved or not, facing Sam and Dean somehow seamed easier.

Quietly making my way down the steps, I stopped in the war room, just before the entrance to the library.

Sam was the first to look up, he was taken aback in shock before he got his brother's attention. Not knowing what to do with my hands, I shoved them in my jacket pockets.

"Andy" Sam sounded almost relieved, and it made me want to believe he was being genuine, but at the moment I didn't know who to trust.

"Samuel" I greeted, keeping both men in my sights.

"When we came back from the case and you weren't here.... we tried calling you" Sam glanced at Dean who was staring at me.

"I was a little busy at the moment" I defended.

"Andy" the gravely voice of Castiel appeared from behind me, and I spun so I was standing in such a way that I could see both parties. "Where were you?"

"Why Castiel, scared you'd lose your weapon?" I watched as he stiffened, his entire demeanor changing. "So it is true"

"What?" Dean stepped forward. "What is she talking about Cas?"

Castiel didn't reply, instead he was studying me, I decided to answer for him "heaven created a seventeen year old ruse in order to deceive me into being their super weapon"

"That true Cas?" Sam watched the situation carefully.

"Are the two of you in on it?" I turned slightly to face them, the Winchester boys looked affronted at the accusation.

"Why would you think that?" Dean folded his arms across his chest "we took you in and treated you like family, if we were in on it do you really think we would do that?"

"I don't know, Castiel was perfectly willing to play the part of father, telling me lies all the way" I looked at the angel who had a contemplative expression on his face.

"How did you find out?" Five little words was all it took for me to believe what Lucifer had said about the angels in heaven.

"Doesn't matter, you faked my whole life, my 'mom' was really an angel and you just lied to me for months" I glanced between the two parties.

"You were not meant to find out" Castiel admitted

"Cas!" Dean shouted

"You don't understand Dean" the seraph began to explain. "She will be more powerful than Lucifer ever was, Nephilim destroy worlds"

"She's just a kid" Sam defended. "And whatever comes our way, we can face it."

"I assure you that you cannot handle her power." Castiel's eyes narrowed. "If heaven cannot use her as a weapon, she will be destroyed"

"Get out" Dean spoke in an even tone, an underlying anger just boiling beneath the surface.

"What?" Castiel looked shocked.

"I said. Get. Out." Dean pointed toward the door "we don't hurt kids, and we're not gonna let heaven use her" he growled. "You either follow their lead or you help us protect her"

Castiel's wings lifted, he gave me one last look before disappearing, his choice made.

The bunker was silent, and it was only a moment before Dean rounded on me. "How did you know?"

"Dean-" Sam started, but was cut off by his older brother.

"No Sam, I want to know how she knew about Cas. She disappeared for days, and comes back knowing the truth"

Chewing on my bottom lip, I hesitated in my answer. Dean wouldn't like the fact I'd snuck out, and he certainly wouldn't like that I'm Lucifer's kid.

"I-" closing my eyes for a brief second, I did my best to collect my racing thoughts, my wings twitched. "I learned it from Lucifer"

"What?" Sam's quiet voice startled me, and my eyes snapped open. "You've talked to him?"

"When I disappeared, for apparently a couple of days" I moved to take a seat in one of the library tables, desperately feeling the need to sit so I could process what was happening. "He told me what happened, but he thought you guys were in on it"

"Lucifer? You believe him?" Dean's hands propped up on his hips.

"I didn't at first" I amended "but Castiel just confirmed everything he said" I paused for a beat, before adding "well he thought you two were in on it, but he was wrong"

"What about the demons? They were hunting you" Sam folded his arms against his chest "he could be trying to make you his weapon, even if he told you the truth about Cas"

"He told me there were very few people in the world he couldn't lie to, Sam and myself being a few of them" I adjusted on the table at the calculating gazes the brothers gave me as they processed my words.

Sam eyebrows furrowed "you're his daughter, aren't you" he realized.

Smart man.

Dean's attention snapped to me from where it'd been on Sam, his eyes widening in shock, before they hardened.

"You guys are starting to regret keeping me alive huh?" I looked away, not wanting to see the looks on their faces.

"Hey!" Dean snapped "you're family kid, and we're gonna protect you from whatever wants to come our way"

I finally mustered up enough courage to return my gaze to them, and they didn't have hatred or disgust like I thought they would, they didn't even have a weapon out, only matching looks of determination.