Stiles wants Derek to be happy.
So he leaves the older man alone.
Leaves him alone when Ms. Blake comes by with a faint blush on her cheeks as the teenagers file out with small curt nods. As the door slides shut and Scott gets a slightly perturbed look on his face. Stiles leaves Derek alone because in doing so it makes Derek happy. And Stiles really really wants the man to have as much happiness as Ms. Blake is willing to give him.
So instead of crowding around the small table in the loft working out plans and preemptive attacks he sits on the floor of Lydia's bedroom. Plush carpet cushioning his tailbone that is still slightly sore from being thrown across a motel by a hallucinating Scott.
Instead of egging Derek on pulling snarls and rolled eyes out of the broody werewolf he's leafing through an ancient witch grimoire. It had been a present to Lydia and Stiles from Deaton. A book handed to them grimly while Scott sat on the exam table clenching his hands mouth pulled tight after apologizing again and again for trying to hurt his friends.
Instead of skirting around Derek and Scott, as they tried to patch up whatever hole had burst through their tentative partnership, he sits with a notepad on his knee. While Lydia cross references a symbol neither one of them can recognize.
And it's because of this. Because Stiles wanted good for Derek. Wanted to put distance between them and help Derek find what was missing that Stiles in the end destroys everything.
All it takes is a single charm. A single harmless charm that creates a tiny fissure in the happiness that Derek barely held in his hands. It turns into a chasm that breaks apart every tentative put together relationship. That explodes through the false calm that had settled over the town.
It's all his fault.
All of it.
He thinks as he sits on the ground of an abandoned warehouse. Every last horrible thing that has happened in the past two weeks is his fault. All the blood, the betrayal, the deaths were his fault.
All of it really is his fault. From the very beginning it's always been his fault. He corrupts what he touches.
It's his fault that Scott was bitten.
It's his fault that Scott can't be with the girl he loves because he listened to Stiles all the months ago.
It's his fault that Allison's mother is dead and that Derek has her blood on his hands. All because he dragged Scott out of his house when he just wanted to sleep.
It's his fault that the alpha pack had come slinking around the town, searching for the newly made wolf. The beta that would climb to become an Alpha through peace and love and moral strength.
It's his fault that Erica is dead and there is a gaping hole inside of Boyd's chest. Simply because he couldn't wrestle is curiosity into submission.
And now this is his fault too. The look of utter betrayal, of heart break, of another person he though he knew and loved using him to kill innocent people. The pale trembling hands stained with red, the ripped shirt, the small whine that is torn out his throat as his last two remaining beta's crumple to the ground. It's his fault that Derek is standing in the middle of the warehouse with blood dripping off his fingertips. It's his fault that Ms. Blake his standing in front of him with a snarl curled up on her lips as electricity jump between her knuckles.
"I'm sorry" he gasps out between labored breaths. There's a hole in his side, the slick slide of thick blood is making him light headed. He means to say it everyone, to all his friends. The half human forms unconscious on the ground. To Derek who is barely standing on his feet. To Scott who is leaning against a pole a few feet away from Derek. Allison, who grip is too tight on her daggers, bow broken and cast aside a long time ago. Cora, who is breathing ragged bound in a circle of mountain ash, claws stained with her own brother's blood. Isaac, who stopped breathing 30 seconds ago. Boyd, whose unmoving form looks too much like Erica when Derek brought her body home from the vault.
"Not as sorry as you're going to be" Cora snarls trying to move again against the mountain ash. Stiles is glad now that Lydia had declined to go with them. That she promised she would join them later in the battle. She had decided to stay back with Deaton to make sure the body of the alpha's stayed dead. That had been a brief moment of dark happiness. Their celebration stained by the knowledge that none of their pack was untainted now, all of their hands were stained black with death and red with blood.
Lydia would've slapped him for saying sorry, war in progress be damned. She had told him once late into the night after Stiles had walked into the loft uninvited when he thought Derek would be alone, that he had nothing to be sorry for. The universe would have found a way to make everything happen and maybe it would've been worse. So he never had to apologize.
But right now he had to be. He had to grovel because of his need to help, to stick his nose where it didn't belong, he broke Derek again. Created a hole that will never be able to filled.
"I should be thanking you Stiles" Ms. Blakes voice is the air right before a lightning storm. It jumps around in the warehouse and draws up the small hairs on the back of your neck. "Because of your little charm I was able to get this process over much quicker. I didn't have to keep sullying myself with this monster."
Ms. Blake was a dirty bomb, a silent attack, a fallout plan hidden by the Alpha's. She was an IED that was unidentifiable until it was too late. Till it had exploded and everyone was too stunned to react.
A witch with a deep seated rage and hate for the wolves that lived inside some humans. A hate that was cultivated through years of dictation and a family that was ripped away during a brutal family feud. A Kate with unimaginable powers.
Cora was a snake in the grass, a wolf in sheep clothing. The irony of that statement is lost somewhere in the will power Stiles exerts to keep himself conscious. Brainwashed by the image of power and greed.
All of this is Stiles fault, this is his damage. The blast wave from that one night over a year ago. Stiles wasn't too sure he would be able to stomach looking at the wreckage once the smoke and fire cleared.
Pushing his body upright against its protest, against Scott's yells, and Derek's demands Stiles stares at Ms. Blake head on. "I'm sorry that I cast that charm. That I sought out other people like me. That I exposed the truth of you to the pack. Because now you're going to die and more blood with stain our hands. I'm sorry that another soul will land on your backs. That we will have to face another horror when we close our eyes." Stiles speaks as he moving forward, one hand grasping at the wound on his side. The other is busy carving a ruin into his palm, finger nails drawing blood, breaking apart the skin.
Her laugh is a crack of lightening in the air, the wolves flinch from the sound. Stiles doesn't pause just keeps sliding his feet against the dirty floor. "I'm sorry that you gave something to Derek that he needed then turned around and tore it out with such violence that it will resound until the day he dies. I'm sorry that his kin betrayed him and left him bereft of something that is so essentially to humanity that he will be driven farther into the darkness."
There is an arm length between them now. Ms. Blake is thrashing and screaming her hair flying wild, bolts of electricity shooting from her hands only to fizzle and die before they reach the living. Her mouth is opened wide with anger with fear. She had been too distracted. Caught up in her own power trip, in her need to beat down Derek, that she hadn't noticed the silent movement behind her. Hadn't noticed a flash or strawberry blonde and a muttered spell. She was trapped by her own arrogance.
"And I'm sorry that I corrupt and warp everything that I love" there's a red smear across Ms. Blake's face as she crumbles to the ground. As the sparks jump from her body to between Stiles knuckles. A hate and rage that runs so deep inside a once breathing body slams into him and it nearly swallows him whole. The ruin on his hand disappears as the body hits the ground lifeless.
There is a new surge of power inside Stiles. He can see himself in his friends' eyes. He can see the way his eyes turn black then burst with a brilliant bright white light. It's his body taking in, processing the tainted magic, and then converting it to match Stiles's soul. He watches himself from Derek eyes as Lydia slides her hand into Stiles. She steadies him as the ruin carved into her palm mingles with his blood and regulates him. Watches as a connection is formed between him and the girl he had once loved for so long. And the power that is too much for one person flows between the two of them. Watches as their powers join and become one within two people.
Stiles is sprawled out, boneless and graceless, on the couch as his friends file out. He watches silently as they one by one disappear to the outside world. As Isaac grabs both Scott and Allison's hand and talks about a pizza place he's certain makes the best pie in Beacon Hills. As Boyd wraps his hand around Cora's. It had taken months and two escapes before Lydia and him had discovered a spell that erased the Alpha's effects on Cora. It had taken months more for Derek to begrudgingly admit he likes that Boyd and his sister feel into such easy camaraderie. As Peter and Lydia bicker about the effects of sage on malevolent spirits. Lydia flipping her scarf into Peter's face as they disappear around the corner of the door frame.
It had taken months for all this to happen, for the blood to wash away and the monsters to fade out of nightmares. Had taken so long for everyone to smile, to brush by each other casually without flinching, to reach out and pull someone into a hug. It had taken months of Stiles sitting in his room eyes red from lack of sleep, of avoiding his friends, avoiding Derek. Of a near fatal incident involving a rogue banshee that left Stiles powerless and helpless for weeks. Before he burst through the doors of Deaton's office face wet from tears and begging for help. Please help, I can't do this anymore, I can't…I can't.
It had taken time and patience. It had taken a plant that had been dying from disease and neglect for Stile to realize he wasn't corruption. It had taken sitting up all night staring at the plant trying to will it to get better. It had taken six panic attacks and Scott begging him to please please Stiles just don't be dead. Please will you do that for me, don't be dead. It had taken Derek's eyes turning red as Stiles gasped back from the borderlands of the place where the living were not allowed. Of understanding his role in the world, for the connection between him and Lydia to solidify and become apparent of what exactly it was. To know one day they would be protectors and guidance for young stumbling supernatural creatures. Deaton in two different forms. For Derek to gather him up in his arms and beg him to never leave him again even though there were seven other people in the room with them.
It had taken all that and one night under the full moon sitting on the steps of the still charred Hale house. Of the pack, his pack, wolfed out and playing like little pups together. It had taken them blood and battle and sacrifices and being tracked down by an enemy that was nearly too strong for them to take. In the end it was the bond between the pack that had saved them. That had allowed Lydia and him to draw up enough power. Because of the pack's love and bond to each was strong enough, as horribly cheesy as it sounds, to destroy their enemy.
It had taken every last single instance and crispy brown leaves blooming into luscious green foliage for Stiles to realize that he did not destroy. He certainly held that power but instead he chose in the end to build and create.
After all that as he sat on the couch, as Derek ambled around the loft putting away half empty bags of chips and tossing out pop cans, Stiles smiled. Because as Derek sat down beside him, their hips and shoulders pressed firmly together, heavy and exhausted from the long day Stiles could see the smile on the older man's lips.