Author notes: The mandatory coda piece, because Show didn't properly finish this story thread. Title shamelessly stolen from Led Zeppelin. Betaed by tanaquispn.

Nobody's Fault But Mine

By Scribblesinink

Sirens are nasty things. That it got to you is no reason to feel bad.

Bobby was right, of course. But Dean knew that getting suckered by the siren wasn't why the mood in the car had gone from uncomfortable to oppressive to unbearable. And he knew Sam knew it too.

Even the radio failed to banish the awkward silence, no matter how loud Dean turned up the volume. In the end, he reached over and switched it off altogether. Led Zeppelin had a bit of a sour taste to it at the moment, anyway.

And the siren had it wrong: Dean didn't need his little brother to be a clone of himself, with a love for classic cars and a knowledge of obscure rock details. Didn't need him to share ogling strippers in a bar, either—hell, he'd miss Sam's disapproving scowls too much if he did. And he certainly didn't need Sam to be the little brother who looked up to him. Not anymore—at least, he didn't think so.

However, he did need Sam to be someone he could trust. And right now, Dean was no longer sure he was.

His shoulder twinged, the spot where Bobby'd stabbed him itching under the jacket. Bobby had taken care of the cut right after disposing of the siren's body, and Dean knew it would heal up soon. Yet at the moment, the injury bothered him. He shifted, trying to find a more comfortable position, and winced as the gesture forced stiffened muscles to stretch.

Screw it; there was no way he was gonna drive all the way to southern Oklahoma tonight. He hit the blinker and took the first exit that came up.

Sam started. "We there already?"

"No." Dean slowed down, looking for signs that advertised motels. "I just don't want to drive today." He felt Sam's eyes on him.

"I can drive."

"No."

He found a Days Inn that advertised rooms starting at $39.95, and that was good enough. He turned in the parking lot and told Sam to wait by the car.

A few minutes later, he returned from the office with two keycards for Room Twelve, which turned out to be on the ground floor. Good. His ribs protested whenever he took a deep breath; his knuckles were raw; and his face throbbed where Sam had gotten a good right in. Last thing he wanted was to have to lug his stuff up some rickety staircase.

The room turned out to be plain but functional. Dean dropped his duffel on one of the beds, automatically picking the one nearest to the door and leaving the far bed for Sam. Without speaking, they went about the usual routine they always followed in a new place: salting the windows, drawing sigils over the door, hiding knives under the pillows and in the nightstand drawer. It used to amuse Dean to put an iron knife for protection against ghosts right next to the inevitable copy of the New Testament; nowadays, it no longer seemed so funny.

Finally, they were as secure as could be. "Sam? You want dibs on the shower?"

"Nah, I'm good. You go ahead first."

Dean tried to catch his brother's eye, but Sam was going through his bag and didn't look up. Then again, he didn't need to see Sammy's face to recognize the signs. His brother being all nice and considerate? When he always complained about Dean leaving wet towels on floor? That was guilt talking.

Whether it was guilt over the things Sam had said, or about not mentioning he was talking to Ruby, Dean didn't know.

Dean collected a clean shirt and made his way towards the bathroom. He was reaching around the door to turn on the light when Sam's voice stopped him.

"Dean...?"

Dean glanced over his shoulder; he didn't need Sam to finish. "I heard you the first time, Sam."

Sam blew out a breath. "I know. Doesn't mean I can't say it again: I didn't mean what I said."

"Yes, you did." Dean flicked the light switch, and blinked at the sudden bright glow.

There was a pause before Sam admitted, "All right, maybe I did. A little."

"Good. So did I. A little." Dean was silent for a moment, before leaving the shirt on the bathroom sink and heading back out. "What the hell are you doing, Sam? Ruby might've saved your life, but she's still a demon. And you trust her more than me?"

"That's not...." Sam glanced away and when he spoke again there was that little wobble in his voice that Dean hated—had hated since Sam was four and skinned his knee in a too-rough game of soccer. "You want to know the real reason why I didn't tell you?"

Yes, do enlighten me, Sammy. Dean was wise enough to keep the bitter words to himself. Instead, he sank down on the edge of the bed, suddenly feeling too tired to remain standing. "Please."

For a long minute, Sam stayed quiet, and Dean wondered if he would ever get his explanation.

Finally, Sam took a deep breath. "Because I knew you wouldn't like it. I knew you'd try to stop me."

"Damn right I would." Dean scrubbed a hand over his face, wincing as he touched the bruises Sam's knuckles had left. "You can't trust her, dude. Maybe you think she's helping you, but she's not doing it out of the goodness of her heart. What if she's just using you?"

"You think I didn't consider that?" Sam had started pacing. "I'm not stupid. But I have to do this. I have this... power. This...psychic crap, as you call it. I can't deny that. And maybe it's dangerous to use. But what if this is what it takes, Dean? To end it, for good? To kill Lilith, and keep the rest of those seals from breaking? I have to try. And you know what? I can look after myself." He didn't add that he'd been hunting without Dean for four months during the summer, or for six more before that, until the Trickster turned back time. He didn't need to: it was obvious in every move he made. And it didn't require the spell of the siren's song for Dean to know that one thing he'd said was very true: the Sam he'd known was gone.

As if Sam knew what he was thinking, he added, "I no longer need you to protect me, Dean. I don't need you to be my big brother anymore."

Dean pushed back up from the mattress. "That's too bad, Sammy. 'Cause you know what? I'm never gonna stop." Sam didn't roll his eyes, as Dean had expected. Instead, he offered one of those soft, half-smiles that always made Dean feel funny inside, and that he never knew exactly how to respond to.

"I know. It's just—" Sam gave a helpless shrug. "I'm sorry I didn't tell you."

"Huh." Dean cocked his head, studying his brother. There was a black bruise on Sam's jaw, and an angry red stripe marked his throat where Dean had sliced him. He swallowed. "I'm sorry I cut you."

Sam made a noise in the back of his throat. "Yeah. Wasn't really you."

"At least I kicked your ass pretty good." Dean smirked.

Sam touched the bruise. "That you did."

"So, wanna tell me who's the better hunter again?"

This time Sam did roll his eyes. "You are, Dean."

Dean grinned. "Just try to remember that... Bitch."

Sam turned away, but not before Dean had caught how his mouth twisted up in a smile of his own. "Whatever... Jerk."

Disclaimer: this story is based on the Warner Bros. Television/Wonderland Sound and Vision/Eric Kripke/Robert Singer series Supernatural. It was written for entertainment only; the author does not profit from it nor was any infringement of copyright intended. Please do not redistribute elsewhere without the author's consent.