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Castiel had suspected for a while now that there was something within Sam that was no longer entirely human. Watching Sam interact with Jack only strengthened his convictions. He had no intention of speaking to Sam about it. Sam had never considered himself fully human, and learning that Castiel agreed could put a strain on their friendship – could break the fragile and tentative something more that was trying to assert itself between them. At least now, that was acknowledged, that the two of them were more than friends, more than brothers. It wasn’t the profound bond Castiel had with Dean, but it was no less important to him, no less precious. Because of that, he’d never looked too hard at whatever it was that he could occasionally feel trying to assert itself from deep within Sam’s soul.
Meeting with Naomi and learning just how dire things were in Heaven had badly shaken Castiel. When he got back, Sam took one look at him and guided Castiel to his room. “Come here. Whatever’s wrong, you can tell me after you’re less freaked out by it.” Castiel didn’t hesitate, lying beside Sam and resting his head on his beloved’s chest. “If you want to talk about it, of course. You don’t have to.”
“Yes, I do. And I will. In a bit.” Castiel closed his eyes and let Sam’s heartbeat and breathing wash through him. As a human, he’d never liked sleeping. Now, he almost wished he could. The main problem with sleep was that there would be dreams, and given what was happening, those dreams would almost certainly become nightmares.
After ten minutes or so, Castiel picked up his head. “I went to ask Heaven for help finding Gabriel. I knew things were bad up there, we were never infinite to begin with and between me nuking Raphael’s followers when I was playing God, the Great Fall and the infighting in the aftermath of it, the war against Amara, and Lucifer’s temper… well. I knew there were few of us left. I didn’t realize just how bad it is.”
“How bad?”
“Very. Counting me, counting Gabriel, there are no more than twelve angels between Heaven and Earth. Naomi wants to help me, despite our history, but they can’t.”
“Wait. Naomi? I thought Metatron killed her.”
“So did I. I was wrong. She was badly wounded and is still healing, but she’s not dead. With so few angels remaining, she’s come out of hiding to try to organize what Heaven can and can’t do. Right now, it’s taking every angel in Heaven just to keep it from collapsing, just to keep the souls from getting loose and becoming spirits here on Earth.”
“Wait, what? I thought the souls were the power in Heaven. That’s why you needed Purgatory when you were going after Raphael.”
“They are. However, without angels to channel that power and direct it, it would explode. A single soul’s power being freed is bad enough. There are billions of souls in Heaven. As it is, the angels remaining in Heaven are slowly burning themselves out to keep Heaven running. Gabriel could stabilize it, if we can find him and convince him to return. Without him, it’s a time bomb. Even one angel currently in Heaven leaving would potentially destabilize it to the point of death.”
“Wow. That’s… no wonder you were so freaked out. Finding Gabriel just became even more important for you.” Sam hugged Castiel close. “And Naomi would send anyone she could spare to help search for him, she just literally doesn’t have anyone?”
“Exactly. Now I’m torn, myself. I wouldn’t be enough to stabilize Heaven, but I could share in my brothers and sisters’ last stand. The problem is that if I go up, there’s no one down here to find Gabriel, or to intercede with… wait.” Castiel’s brow wrinkled. “Naomi asked me to intercede with the Nephilim.”
“Well, yeah. Jack’s your son, you and he have that bond, and he’s got grace, so he might be able to help.”
“And he has functional wings, which makes him a better choice to search for Gabriel, freeing me to go help bolster Heaven. That, I understand. What I don’t understand is why she said Nephilim. Metatron tricked me into killing the last of them before Jack.”
“Or so he claimed, anyway. So…?”
“So Nephilim is like cherubim or seraphim. It’s plural. Jack is only one nephil. I would have felt it if there had been another one conceived, and she must assume I know the other and that they… would be receptive…” Castiel trailed off, hand clenching in Sam’s shirt as he realized what Naomi must have meant.
That feeling, that power, buried deep in Sam’s soul… he’d been possessed by two different angels, worked closely with another, died and been resurrected by angels several times, and earned the favor of Chuck. Those experiences had added up, left their marks on his soul, and now the power of Sam’s soul had gathered those traces of grace and converted them. It was rare, but then again, most people only ever hosted one angel in their lifetime, and resurrection was meant to be reserved for specific cases. Add in the mark of the True Vessel, his birth to Cupid-made soulmates… Castiel probably should have realized before.
Sam stroked Castiel’s face. “You know what Naomi meant?”
“Yes, I do. I believe. Sam…” Castiel reached up and took Sam’s hand. “I believe she referred to you.”
“Me? No, I know my parents, one of them’s lost in Michael’s universe, the other’s been dead forever. Neither of them were angels.”
“No, but there is another way to get a nephil. All it would take is a spark from me, or any angel, to awaken the grace nestled within your soul.”
Sam swallowed hard. “Lucifer?”
“Among others, yes.”
“What about Dean?”
“Dean’s got the beginnings of it, the channels and structure and potential are there, but he’s never been possessed. Even with the extraction, you’ve still got traces of Gadreel’s grace, and then of course Lucifer’s. Dean doesn’t have that seed grace to build on.”
Sam lay there silently, and then leaned down to kiss Castiel. As he did, the room flashed azure, and Sam pulled back. “Huh. That explains a lot.”
Castiel looked critically at Sam. “You’ve activated… yourself? How?”
“My powers. Ever since Magda, I’ve been experimenting with a few small things, and working with Jack helped. Ever since Jack disappeared, I’ve been feeling a… I don’t even know how to describe it. A call? An urge? An itch? I don’t know. I’ve been resisting it – experimenting with random stuff has way too much potential to backfire, but when you told me about Heaven’s need, it got stronger. Almost impossible to resist.”
“You could. I know you could.”
“I could, but right now, it sounds like Heaven needs me. I don’t know how much use I’d be up in Heaven, but you can give me a crash course on using my powers to help find Gabriel, and then we’ll figure out where to go from there.”