Author's Note: I was actually going to let We Need to Talk about Kevin go untagged, because there wasn't anything I particularly wanted to write. Then SandyDee84 suggested having a go at speculation related to Dean's new friend, so… Here it is. The Season 8 Tag Series has begun. :) I hope you enjoy it!

Thanks to Cheryl for the beta.

Disclaimer: The boys aren't mine. Nor is Benny.

Summary: Someone is standing in the dark watching Sam Winchester drive away. Tag to 8.01, We Need to Talk about Kevin.

The Watcher in the Shadows

Dean Winchester thinks he's so smart.

The vampire who calls himself Benny – at least in this century – smirks as he draws the car up to the curb. He's chosen an old model, a Mustang, because he really doesn't have time to figure out the new fancy cars with dashboards that look like they belong in a spaceship. The woman who used to own the Mustang is lying behind a dumpster two towns away, sightless eyes staring up into nothing.

He's a couple of blocks away from his destination, but he can already smell it, sharper and clearer than the thousands of other scents assailing his nose.

Benny locks the car and starts walking.

The ones who think they're smart are the easiest. Dean's so used to saving the world, so used to facing enemies stronger than the human mind can comprehend, that he's practically forgotten that the smaller dangers are worth worrying about.

He's lucky it was Dean who got sucked into Purgatory. He's heard enough about Sam to know that.

Sam's not like the others, Lenore said the last time saw her, something very close to respect colouring her tone. Sam understands. Sam sees that all vampires aren't evil. Then she looked straight at Benny – Benny, he's going to have to get used to that name. He wouldn't kill me, even when I asked him to. Even when I told him I couldn't resist. He thought I could be saved.

Sam sees, Eli repeated, eyes glinting with cold malevolence. Benny met his father's gaze in the darkness of the Purgatory night and nodded.

Sam sees.

Be careful around him. That was what Eli meant. Sam sees the good and he might see the bad. Sam will trust an enemy so he might doubt a friend.

But Dean's world is black and white, just like Eli said. Get him to trust and he'll forget he ever had a reason to doubt. Dean doesn't give serious credit to the idea that a vampire who betrayed his friends for Dean would just as easily betray Dean.

Benny licks his lips. He can still taste her blood, the former owner of the Mustang. His first taste of human blood since Samuel Campbell hacked his head off all those years ago.

Benny thrills with the anticipation of revenge.

He vaults easily over a fence to Sam's street. This close, he can smell it even more strongly. Sam's blood. After everything he heard, he expected it to smell rank and foul, like a demon's blood, but it doesn't. There's a lingering something that's reminiscent of Azazel, but the reek of Archangel is far stronger. That, and something new, something fresh, that probably comes from being torn apart and put back together so many times.

But the strongest impression Benny has, so strong that it overpowers everything else, is that Sam's blood smells like Dean's.

Benny breathes deeply, like he's inhaling the scent of a fine wine.

For a moment he thinks longingly of champagne sparkling in crystal flutes. Marie Antoinette kept a fine table… Such a shame she couldn't keep her head.

Such a shame the world has no more Marie Antoinettes.

Sam's blood smells more tempting than anything Benny ever tasted in the Bourbon court. He hasn't even bothered to check the house number. The scent was enough to guide him.

He's near enough now to sense the blood thrumming through Sam's veins and feel every beat of Sam's heart. One woman wasn't nearly enough to make up for fifty years' deprivation in Purgatory. All Benny wants is to walk into the house, past the conflicting and bothersome scents of the girlfriend and the dog, seize Sam Winchester, and feast.

Benny forces himself to stay calm and think about his plan.

This isn't only about revenge.

Revenge is certainly a reason – and an important reason. Lenore told Sam that the rest of her nest had been killed, but she didn't tell him everything. She didn't tell him who it was who did the killing.

She didn't tell him how many deaths were on Samuel Campbell's head.

This is also about righting a wrong. Sam and Dean are all that's left of Samuel Campbell's bloodline. The spell Benny taught Dean isn't the only resurrection spell he knows.

Benny's never had a job he liked as much as this. Sam and Dean Winchester. Even individually, either of them would be a special treat. Together…

Together, their blood has demon and Archangel, vampire and phoenix, Heaven and Hell, Purgatory and the Cage…

Together, their blood will be alive with all the fierceness and intensity of their bond, the bond that angels and demons and monsters and humans have tried and failed to break. The bond that defeated Lucifer.

Benny – he laughs at the innocuousness of the name – stands in the shadows, staring at the house.

Dean was so easy.

Dean sees Purgatory as pure. It is, in a way. Purgatory is adrenaline and animal instincts. Purgatory is the terror of the chase and the thrill of the hunt. Purgatory is the deepest, most base, most feral part of every living soul.

Benny supposes that could be considered pure.

At any rate, a year in Purgatory has taught Dean to live in the moment, to live for the moment. He didn't ask many questions earlier, and he asks none at all now. He doesn't tread in grey areas, not even as much as he used to, and once he decided Benny was on his side, it wasn't long before he stopped thinking about his new ally's motives. He never wondered why Benny asked if anyone was working to get him out of Purgatory. He never asked why Benny so often mentioned Sam's name and then stopped short as though he thought he was touching a difficult subject.

He didn't realize Benny was toying with him.

Now Dean's scared, more than ever, of his brother's abandonment. Dean's not a fool: he knows the year in Purgatory changed him. Maybe he even understands how it changed him. And there's a part of him, a part he thinks nobody knows about, that's terrified that he's turned into something Sam Winchester will reject.

The entire world knows that Dean Winchester has only one way of dealing with fear.

Benny's smile widens as he watches the dark house. He steps further into the shadows when he sees a light go on in the bathroom window. It's going just as he anticipated.

He reflects smugly that he's got Dean where he wants him, and now all that remains is Sam.

Sam is good, Lenore said. Sam is different.

Nobody's different, Eli scoffed.

Sam Winchester is dangerous, the Alpha Vampire warned when Benny spoke to him on the phone earlier today. Don't make the same mistake everyone else did. Don't underestimate those boys.

Benny snorts. He hasn't underestimated Sam at all. He's got the younger Winchester boy's measure. He's heard the stories. He understands what everyone else has done wrong and what he's going to do right.

That's why he spent so long playing on Dean's insecurities.

Benny isn't going to break Sam Winchester. He's going to let Sam's brother do it for him.

The front door opens and a figure steps out. He's tall, but that isn't what strikes Benny the most.

Sam looks… gentle. Soft. Pliable. He looks like a man with a house and a girlfriend and a dog, not like the hunter who defeated Lucifer. He looks weak. Benny can't believe that this isthe man who won a battle of wills against the Devil.

Benny suppresses his laughter. His plan is perfect. This is going to be like sucking blood from a baby.

Sam comes down the steps and stops by the car. The Impala, sleek and black and gleaming. Benny's heard all about it from Dean.

Benny watches, amused, as the hunter's large hand rests on the hood. The vampire shakes his head, turning away for a moment to glance at a bat that's come to rest in a nearby tree.

When he looks back, something's changed.

Sam's still there, still wearing the same clothes, still fumbling with the keys. Same silly haircut. Same too-large body. He still looks gentle and soft. But he doesn't look weak anymore. He looks more incomplete, and yet somehow stronger, and his eyes sparkle with something Benny, with all his centuries of experience of humans, can't identify.

Suddenly Benny knows what the change is, knows because he can scent it – the fierceness, the intensity, the love – in the blood pumping through Sam's body.

Sam isn't Sam anymore. He's half of Sam and Dean.

Benny, cold-blooded though he is, shivers in the night air. This wasn't part of his plan. He wasn't prepared for this. He barely even understands what's happening. All he knows is that a moment ago he saw easy meat, and now he sees strength and courage and a core of steely determination that he thinks even he might not be able to overcome.

Benny's breath catches as, for the first time, he wonders what it'll take to turn Dean from Dean into Sam's other half, and what it'll be like when that happens. Will it happen as soon as Dean sees his brother? Will it happen the first time he sees Sam in danger?

And if that happens, if Sam and Dean become Sam and Dean, will Benny's plan crumble in the face of Sam's loyalty and Dean's protectiveness and the legendary Winchester bond?

For the first time in his long, long life, Benny is afraid.

After all, Lucifer and Michael had a plan, too.

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