Goddamn it, Stiles.
Of course it was Stiles! Of course it was the one person Derek couldn’t stand to lose. Of course. Of fucking course.
Polish was the only language Lydia couldn’t wrap her tongue around, and one of the rare few about which Derek was completely ignorant. But when the creature newly terrorizing Beacon Hills turned out to not just be a vampire, but a goddamn fucking upior, Stiles piped right up with a slew of information—horror stories, really—he learned from his babcia.
They tracked down who the upior was shortly afterwards, and when Scott tapped the name on the computer screen, he said, “I…have no idea how to say that, but that’s her name.”
Stiles laughed and said, without missing a beat, “Oh, that? Katarzyna.”
Then he dropped like a stone.
He woke two days later to a bruising mark on the side of his neck and an exhausted, worried, out-of-his-mind Derek at his bedside.
What his babcia never told Stiles—and what the Pack later learned with Deaton’s help—was that to name the upior was to mark oneself as its next, and highest priority, victim. Stiles’ two-day nap transformed enough of his life-force into an upior beacon for it to track him at its leisure. Hell, apparently if it wanted to, it could just wait and finish Stiles off through the mark on his neck without ever making an appearance.
But Pack wouldn’t let Stiles go without a fight. They disbursed to form a plan, leaving Stiles in Derek’s very capable hands.
When Derek returned to from getting take-out, he found his very exhausted, very human boyfriend standing in the middle of the loft, and it reminded him enough of the Nogitsune for his stomach to twist. He nearly dropped the bags of food until he caught Stiles’ scent and realized nothing, aside from the upior mark, was amiss.
“You should be in bed,” Derek said, setting the food a kitchen counter.
“I’ll be fine, Sourwolf,” Stiles said. He rolled his shoulders, then turned his attention back towards the large glass windows overlooking downtown. “You should help the others. I’ll just, you know…” He made a vague, unspecific motion with his hands, and cracked a grin.
Derek rolled his eyes, but closed the distance between them with a few purposeful strides. He rested his hands on Stiles’ waist and leaned close enough to scent his temple. “I have no idea what you’re referring to, but the answer is no,” Derek grumbled. When Stiles scratched lightly at his scruff, Derek leaned into it, ultimately taking Stiles by the wrist and kissing his palm. “And I’m not leaving you alone. If that bitch shows up, I’m going to rip her fucking head off.”
With a smirk, Stiles said, “I know. Worth a shot, though.”
“What, sending me away?” Derek snorted and griped Stiles’ a wrist tighter. He eventually laced their fingers and pulled Stiles against his chest. When he went willingly, as he always did, the anxiety building in Derek’s wolf quieted some.
“No,” Stiles said quickly. “Never. Just, you know…I, uh, I planned to do this alone.”
Derek clutched their joined hands and pulled away to fix Stiles with a dangerous and incredulous stare. “…do what alone?”
Stepping forward where Derek had stepped back, Stiles clung to the werewolf and pressed his face against his shoulder. “Kill the upior,” Stiles admitted voice muffled. Derek stiffened in response, but Stiles just held him tighter. “And it’s good to know you’ll rip her head off, since that’s how you have to kill her if I can’t do it.”
“If you can’t…?”
“I have to try to stake her,” Stiles said. “If I can stake her myself, I’ll recover faster.”
“Why don’t I just hold her down and let you do that, then?” Derek asked. He rubbed Stiles’ back with broad strokes until he melted against him, leaning his weight into Derek’s steadfast, supernatural form.
Stiles tangled his hand in Derek’s shirt and tugged a little helplessly. “Upiors have a, like, a biological compulsion to rend lupines. I only want you involved as a last resort. I can’t…I’m human, Derek. I can’t protect you.”
“We’ll call the others. They’ll help.”
“Too late,” Stiles said, pulling away from the wolf. He forced distance between them and walked towards the window again. “She’s on her way.”
Derek’s eyes flared and he growled almost involuntarily. The mark on Stiles’ neck darkened, but the human didn’t seem to notice or care.
“Make yourself scarce,” Stiles hissed over his shoulder. “I’ll call for you if I need you.”
“Goddamn it, Stiles!”
“Yell at me about it later, Derek. Just go!”
So Derek listened, launched himself and dove, sliding into the kitchen behind the counter that served as the breakfast bar. There, he breathed deep and slowed his racing heart. Above all else, he trusted Stiles. As stupid as his plan seemed, he trusted Stiles to not sacrifice himself in front of Derek, or to make Derek hold his bleeding, lifeless corpse. He trusted Stiles to call him when he was needed.
Wind blew, despite all the doors and windows being closed, and the loft flooded with a new, unfamiliar scent. Like damp earth and blood and decay. A third heartbeat thudded low and slow—the upior.
She said something Derek recognized as Polish, and her voice was gentle and soft. It reminded him of a mother with a sick child, how rolling and smooth it was, despite the rough edges of her language. A shiver slithered down his spine. Stiles sometimes muttered similarly in his sleep, and he hated the comparison.
Stiles answered, a sneer, also in Polish. Hard and challenging, and his sneakers squeaked a bit with his steps. He made a declaration, and his heartbeat skipped—a lie. His fear, a painfully familiar and bitter sharpness, tainted his scent. Derek’s claws extended involuntarily in response.
Derek’s sideburns grew in tuffs down his face with a negligible itch, his ears extended to points, and his fangs descended to fill his mouth with their razor points. His wolf wanted, needed, to protect Stiles, and Derek wasn’t going to keep that part of him subdued for much longer. Not with how Stiles was slowly growing more fearful, not with how his heart started pounding.
The upior said a few more words, then Stiles sprinted. Derek heard the end table in the living area crash to the floor. Another whipping of wind and fabric, and Stiles sprinted again. Again and again, Derek heard Stiles dash from one point of the loft to another, tearing through furniture, and at every point, the upior intercepted him with its teleportation. The wolf leaned carefully around the edge of the kitchen island.
Stiles stood in the center of the loft, the home they’d made of it—together—in complete disarray. But he stood boldly facing the upior, who looked nothing more remarkable than a regular woman, and kept himself steady. Only Derek, with his werewolf senses and intimate knowledge of Stiles, could tell how utterly terrified he was.
“They’re gone,” Stiles murmured. “They’re all gone. What the fuck?”
When she smirked, Derek saw her jagged fangs glint in the light, and from behind her back she revealed a bundle of stakes. She dropped each sharpened wooden piece to the floor in careful succession, and when each one hit the floor with a hollow thunk, Stiles flinched. His breath was a little unsteady, and he managed some modicum of his usual sarcasm to answer for the stakes he’d hidden, and she subsequently collected, around the loft.
They exchanged more words, the upior smelling smug, which clashed with Stiles’ anxiety. But the longer they stood there, the more their scents mingled, and the harder it became for Derek to distinguish them. The mark on Stiles’ neck had darkened, no longer bruise-like in its color, but black, like necropsy.
“Come and get me, bitch,” Stiles muttered.
The upior lunged and hit Stiles hard, fangs bared and claws extended.
He let out a soft oof with the impact, and when they hit the floor, they slid. Stiles wrestled her, keeping her jaws from locking around his neck with an iron-grip and trembling arms, then threw her off after a well-aimed jab of fingers in her eye.
She wailed, a shriek that rattled Derek’s skull and numbed his ears, and rolled off of him. Stiles, on hands and knees, scrambled towards the kitchen. He started climbing to his feet just shy of Derek’s hiding spot, but the upior pounced and knocked him down. She dug her claws into his shoulders, and hissed her easy victory, leering over her quaking human prey.
But they’d landed within striking distance of Derek.
Stiles managed to meet Derek’s eyes, and the wolf didn’t need a signal or prompting. He launched himself at the upior with a roar, and his claws sank easily into her unsuspecting flesh. He tore, and bit, and clawed her as they tumbled away from Stiles, but she didn’t go down easily. The rake of her claws, the bite of her teeth—their stinging and the warmth of his spilled blood were easily ignored in favor of his wolf succumbing to protect protect protect.
He pinned her down with his superior weight and dug through her chest cavity. Each strike of his claws splattered blood, more blood than a human body could reasonably hold, and he didn’t stop until she went limp beneath him. Tearing through flesh and muscle, he soon reached her ribcage. He gripped the ruddy bone and pulled, snapping her sternum and its attached ribs with a satisfying crack. Then he buried a clawed hand into the thick meat of her heart, and his wolf positively howled.
Chest heaving, the wolf looked up from his prey to his mate—boyfriend for Derek when he was in his right mind, but mate when he acquiesced control to the wolf—and found his condition worrisome. Stiles was pale, trembling, and blood stained his shirt where the upior’s claws had dug into his shoulders.
“Her head,” Stiles said. “You have to rip her head off. Decapitate her, or she won’t die.”
So Derek did, unceremoniously. Grab, twist, yank. Her neck snapped as easily as her ribs had, but he grunted with the effort of popping tendons and pulling apart muscle. He dropped the severed head in the puddle of blood quickly spreading from the neck. He lifted himself off the body, and had taken less than three steps from the corpse before his bloody, aching arms were filled with Stiles.
“You did it,” he breathed into Derek’s neck. If the contentedness and relief rolling off of him in waves was any indication, Stiles didn’t care that Derek was covered in the thick, soupy gore of a mangled upior. “You actually ripped her fucking head off.” His laugh was a little manic, a little hysterical, but he gripped Derek tighter.
“I told you I would,” Derek growled. Heedless of the blood, he rubbed Stiles’ back and pressed a kiss to his temple. “Are you alright?”
Despite the blood and the fear and the death that still hung heavy in the air, when Stiles kissed him, Derek’s world shrank to that one, single point. Stiles, safe, in his arms.