Is it taking over you?

'Cause it's taking over me.

And there's nothing I can do, 'cause it's the wolf inside of me.

The Hale house was, as it was almost every weekend, filled with the raucous laughter of teenagers unbound by adult supervision. Well, there was Derek, but he wasn't that much older than the rest of them, and it's not like he would actually do anything to quiet them anyway. Everyone knew that despite his growling and frowning, Derek loved having his childhood home once again bursting with life.

Plus, he wasn't there at the moment to shut them up even if he wanted to. They had collectively voted the alpha to go pick up the pizzas for the evening, so he was currently not present to yell at Erica for spilling Dr. Pepper on the new carpets. However, Stiles reminded her urgently, he was due to be back any minute, so she had better hurry up and get it clean.

Leaving Erica to her own grumbling devices, Stiles went to the kitchen to grab some other snacks for the pack. It was as he was juggling three bowls of chips, tottering back to the living room, that the front door slammed open with a crash that indicated the first hole in the brand new dry wall.

Peaking over the towering snacks in his arms, Stiles called out, "Glad to see you, too, Sourwolf. Who shoved a mountain ash stick up your ass?"

All he got in return was a low growl that had everyone going silent, watching Derek with carefully curious eyes. No one mentioned that he didn't have any pizzas with him, too busy watching as he slowly and deeply inhaled, eyes fluttering shut for a lingering moment before snapping back open with a distinct red hue.

Before Stiles could even process that he had crossed the room, the bowls were swatted out of his hands, clattering to the floor and covering the carpet in chips and crumbs and cheese powder that would be a bitch to get out later.

However, he didn't dwell on the mess for long, because the very next second his back was pressed against the nearest wall and 200 pounds of muscle-y werewolf was squeezed tightly all along his front. Stiles saw red eyes flash brighter, and then he was lost in a whirlwind of forceful lips and hot tongues.

Beyond Derek's quiet growls and his own moans, Stiles vaguely registered shouting and loud footsteps growing fainter, eventually leaving them blessedly alone.

Derek's hands were everywhere, holding his face and neck in place as he took control, rubbing over his shoulders and chest as he pushed Stiles harder- almost painfully so- into the wall behind him, stroking down his stomach and sides as he nudged them under Stiles' t-shirt, digging his thumbs into the firm skin below his navel and massaging it until Stiles was a writhing mess, moaning around the tongue in his mouth. Had it not been for Derek and the wall so closely pressed on both sides, he surely would've fallen to the ground in a puddle at Derek's feet already. Slowly, those hands slid around his waist, caressing the skin just above his sweatpants before slipping down, underneath the fabric. They kneaded into his ass cheeks and gripped them firmly through the boxer briefs, squeezing and using the hold to drag them impossibly closer and Stiles was gasping into Derek's mouth, not even trying to keep it a proper kiss anymore.

Derek released his hold on Stiles' mouth, and Stiles let his head fall back on the wall with a vaguely painful thud, and then Derek was kissing and sucking along his jawline and under his chin. The way he growled when Stiles bent his head back further went straight south, and the vibrations pulsing through his throat with each of Derek's noises seemingly reverberated through his body, making his fingertips tingle and his stomach churn wildly. The hands under his sweats disappeared, and Stiles moaned at the loss for not even two seconds before they were gripping onto his thighs and hefting him up into the air, encouraging his legs to wrap around Derek's waist as best they could.

Stiles clutched at Derek's broads shoulders, then used one large hand to bring Derek's lips back up to his. He didn't even register the movement, but soon Derek was letting them both fall onto a bed, which Stiles was completely on board with.

Not a moment later, Derek was suddenly missing his jacket and Stiles was missing his shirt. Stiles' hands crept up to cup Derek's face as they continued kissing, and almost yelped at the heat he felt radiating off of his cheeks. He didn't give it much thought- he felt incomprehensibly hot himself. Plus, he was a bit distracted by the scratch of Derek's stubble as he worked his mouth down Stiles' chest and torso, stopping just above his waistband, lowering his pants down inch by inch.

However, the borderline uncomfortable warmth was enough to jerk Stiles back to his own head, and he decided that, whatever was about to happen, they probably needed to talk about their intentions beforehand. So he fought his way through the steamy, lust and Derek induced haze that was clouding his mind, which was incredibly difficult when Derek was nipping at the skin right above where he ached.

But he managed to do it, rasping, "Derek, wait."

Derek just growled again and moved even lower, lower than anyone else had ever been before.

"Derek-" Stiles breathed. Then, more steady, more demanding, he said, "Derek, stop."

Derek didn't stop.

That's when Stiles knew something was wrong.

He grabbed onto the hands that were slowly pulling down his sweatpants and underwear, pulling them away and pushing at Derek's shoulders. "Derek, cut it out! I'm serious, stop!"

When yelling and shoving didn't work, Stiles pushed himself onto his elbows and crawled backwards up the bed, out of Derek's confused and still animalistic reach. The not-quite-man brought himself to his knees, looming over Stiles.

Eyes wide and breathing fast, Stiles muttered, "I'm so sorry about this," lifted his leg, and drove the heel of his right foot hard into the tented front of Derek's jeans.

Derek howled in pain and hunched over himself, giving Stiles a few moments to launch himself off the bed, out of the room, and down the stairs. By the time he got to his backpack, Derek was roaring in frustration and pain and hurt, and Stiles didn't know what to do. He didn't even know what was happening.

Stiles got his hand around the little baggie inside his bag just as Derek was landing heavily at the bottom of the stairs. He stalked over to Stiles, keeping eye contact the whole time. His eyes were bright red, not even a trace of Derek's rationality left.

His mind was the wolf.

But his body was still the human.

What the hell happened to you? Stiles thought as Derek prowled closer. Then, as quick as Derek's lunging form, Stiles threw his arm out with a handful of mountain ash, clouding Derek in the powder and sprinting off down the hall once again. He didn't really have a destination in mind, but somehow ended up in one of the downstairs bathrooms, locking the door that he knew would do absolutely nothing. For a moment he thought about blocking the doorway with the rest of the ash, but that would just lock himself in and he didn't have his phone to call for help. He could hear Derek making his way down the hall, and then silence.

Forming a semblance of a plan in half a second, Stiles jumped into the bathtub/shower compound just as Derek punched the door open. He held the mountain ash tight in his hand, waiting for Derek to make a move. Just as he had predicted, Derek quickly climbed over the ledge of the tub. They stared at each other for a tense moment, and then Stiles was throwing himself out of the tub while simultaneously throwing the ash onto the floor at the base of the tub. It spread into a line, spanning wall-to-wall and effectively trapping Derek behind it.

Derek immediately tried to follow Stiles again, but bounced off of the invisible wall. His eyebrows furrowed, and his mouth pulled down into a confused frown before he was punching and shoving at the barrier, looking increasingly frustrated and desperate as he couldn't get through.

Seeing the sweat dripping down Derek's face and neck, soaking into the collar of his shirt, Stiles risked quickly sticking his hand inside the tub while Derek was distracted with the barrier. He flipped on the water, making sure it was on cold, and then yanked his arm back out when Derek reached for it.

The man shrank away from the water, but made no move to turn it off, furthering Stiles' belief that he had been taken over by his primal instincts. The water beat down on him and he lowered himself to his knees, covering his head with his arms. Stiles stared, praying to every god he didn't believe in that Derek would snap out of it. Praying that he could. Believing that he could.

He knelt there for at least 20 minutes before Stiles finally shut the water off. Derek didn't move, just stayed on the floor of the tub, shivering and dripping. Stiles waited another few minutes before hesitantly calling out, "Derek?"

He slowly lifted his head, water dripping into his once again hazel eyes, and looked at Stiles with an expression filled with a heartbreaking mix of shame and horror.

"Stiles…" he whimpered. "Stiles, I'm so sorry. I… I didn't…"

And then his face just crumbled and Stiles felt any ounce of fear and apprehension drain from his body as he flung his torso over the ledge of the tub and drew Derek into a tight embrace.

"It's okay, it's okay, you didn't hurt me Derek, I promise. I'm okay, you're okay, we're okay. I don't know what happened, but we'll figure it out, okay? We'll figure it out together."

Stiles continued whispering reassurances to the trembling body in his arms for a long time, stroking his hair and rubbing his back in soothing motions until Derek stopped trembling as much. He was still shivering a bit, however, and Stiles gently guided him out of the bathtub and back upstairs into Derek's bedroom. Derek took a deep breath and clenched his eyes shut. Stiles realized that he had to be smelling their combined lust and Stiles' fear from earlier.

Not wanting him to freak out again, Stiles quickly grabbed him a change of clothes along with slipping on his own discarded shirt, and then nudged him into a bathroom down the hall, telling him to change and then they'd figure things out.

Derek nodded and slinked into the bathroom, gently shutting the door behind him.

Stiles pretty much collapsed against the wall, breathing heavily but quietly, as to not draw Derek's attention. His mind was a maelstrom of confusion and nerves and anxiety, but at the forefront of everything was an intense uneasiness. What could have caused Derek to lose his control like that? And why did he come after Stiles, of all people? Maybe he really needed to release some tension and his instincts recognized Stiles as the least likely to be able to stop him.

Even just the thought of it was like a punch to the gut, but he immediately pushed aside the hurt to make room for concern for Derek. That's what was really important, anyway: making sure Derek was okay and making sure that whatever happened didn't happen again.

The door opened and Derek walked out with his head down. His hair was still damp, but the rest of his was dry and completely in control. Subdued. Ashamed.

Stiles led him down to the living room by his wrist, settling him on the couch, surrounded by the scent of pack and family and love, before going to the kitchen to make him some tea. Kira had gotten them all addicted to it, and now it was always being used as a way of calming the wolves during full moons.

With two mugs in hand, he walked back to the living room, stepping over the chips and bowls still on the floor. That would be worried about later.

Stiles sat on the sofa about a foot away from Derek- close enough to show that he wasn't mad at him or scared of him, but not close enough to overwhelm him in any way.

He waited until Derek was almost finished with his tea to hesitantly ask, "What happened back there?"

Derek exhaled deeply and set his mug on the coffee table.

"I was in the parking lot of the restaurant when a man approached me. He smelled… odd. Like lightning, ozone, electricity. A witch. I asked what he wanted, and he said… He said he wanted me to bring him my pack's hearts." Derek paused as Stiles inhaled sharply, and then he continued, "I don't know if he didn't know how to force me to do what he wanted, or if he wasn't strong enough, but he didn't command me to do it with magic. This guy, he knows everything about us. Everything about what we've been through. I don't know how, but he knows that my anchor was anger. He… subdued the human in my head somehow. He blocked it and brought my wolf instincts to the front. He gave the primal side of me control. He... compelled me to act on the desires of my anchor."

Stiles was suitably horrified, but still confused. "But then… why didn't you act out in anger, like he wanted? Why did you come to me?"

Derek shut his eyes and lowered his head. "Because anger isn't my anchor. Not anymore."

And suddenly Stiles knew where this was going. He knew what Derek was trying to say.

But he had to hear it anyway.

"Derek, what's your anchor?"

There was a pause that seemed to last forever, and Stiles held his breath.

"You."

It was so quiet Stiles could barely hear it, but he did, and he thought back to all of their recent battles. How Derek always stuck close to Stiles. How Derek always went to Stiles first when it was all over, even before his own bitten betas. How Derek always came to Stiles when something was bothering him and how he felt like he couldn't trust anyone else with his deepest demons. How Derek was always subtly touching and scent-marking him, how Derek never pushed him away, how Derek was always the first person to notice when Stiles' laugh was fake and his smile was forced.

How Derek relied on Stiles. And how he made sure Stiles knew that he could rely on him.

Overcome with emotion and not knowing how to express it, he set his mug down and turned fully towards Derek, and when Derek wouldn't look at him, Stiles cupped his face in his hands and turned it. He brought their foreheads together and closed his eyes as he simply breathed for a moment, and Derek let out a shuddering sigh, bringing his own hands up to cover Stiles'.

When Stiles opened his eyes, he saw Derek already staring right back. They held the gaze for a long time, basking in being so close to each other.

"Derek…" Stiles whispered, staying quiet because it felt too important to be any louder. "You're my anchor, too."

The eyes in front of him widened and Stiles stared in amazement at the awe he saw reflected in them. "How?" he breathed back.

"You keep me grounded, just in a different way. You can and will bring me back to myself when no one else, not Scott, not my dad, when not even I can or will. I trust you with my life and so much more. I trust you with everything, Derek."

When the intensity in Stiles' eyes and words became too much, Derek closed his eyes and buried his face in Stiles' neck, breathing in the scent of safety and love and happiness and Stiles.

"I trust you, too," he murmured into Stiles' skin. "I trust you with all of me."

Stiles pressed a firm, lingering kiss to the side of Derek's head, wrapping his arms tightly around the man who meant so much to him, never wanting to let go.

And he trusted that Derek would never make him.