It all comes to a head when Erica decides to leap out at him from beside a vending machine and he flails so hard his fingers cramp on the tab of his newly purchased can of coke. He makes a leap of his own, backwards, and gets drenched in a fizzy spray as his head smacks against the vending machine’s glass and sends something clattering down inside. It's his third Operation: Fragile Stiles mishap of the week and there are still six days to go.
He splutters as the sticky drizzle runs down his face, his anger initially dampened by the acknowledgement that at least it wasn't aimed at his crotch this time, until he realises he shouldn't have even reached the stage of making concessions in the first place.
Erica doesn't seem to see the problem. She bends down to retrieve the Butterfinger that somersaulted over the coil inside the machine with help from the impact of his skull and throws him a victorious grin as she skips away.
He's had it with this game he never agreed to play. He's sick of being the only human who has to put up with this shit, the constant shaving of years from his life as he watches over his shoulder for the next wolfy surprise. Allison might know her way around a bow and arrow and Lydia might have her acid tongue for a deterrent, but Stiles has… weapons. He does.
It's Isaac’s snigger and Jackson’s curling lip that do it.
When they pull up at Derek’s for the next pack meeting, Scott eyes him warily as he reaches into the backseat and withdraws a bag that jingles. An innocent raise of his eyebrows is all the answer Stiles gives him.
In the loft, he climbs to his feet as soon as everyone's accounted for with the bag clasped in a resolute fist. “Fun’s over,” he announces, thrusting his hand inside and unearthing a sorry tangle of tinkling string.
Isaac resumes his sniggering but this time Derek joins in as Stiles curses and tucks himself in a corner to scowl and pluck at the mangle of bell necklaces he’d spent a good chunk of the night before threading together. He'd wanted to use dog collars — and the whole reveal would have gone much smoother if he had — but his empty wallet had whimpered so he'd had to make do with the string he’d found stuffed at the back of a kitchen drawer instead.
Allison eventually takes pity on him and joins him in his lonely corner where he's somehow managed to make things worse.
“Not doing it,” Jackson grunts in that caveman way of his when Stiles can finally wave the necklaces around in the air like little lassos as he’d planned.
“Do it,” Derek orders, and though Stiles appreciates the support, he doesn’t appreciate Derek making it sound more like a dare.
Scott gets to be his first victim, unconsciously keeping his jaw level with Stiles’ in case, God forbid, granting him easier access gets taken as a sign of wolfy submission. As soon as the knot’s complete, he tugs at it with his head cocked like an honest to God puppy, eyeing Stiles with a failed attempt at innocence that’s asking why me, bro? as if the accusation is a scathing betrayal to their friendship. Everyone knows Scott’s the worst offender.
Erica needs no encouragement. She holds perfectly still while he fastens it — again, jaw level — and then starts swaying and jangling around the loft with her arms above her head. (When he next sees her, she's swapped the piece of string for a sizzling red choker to match her painted lips.)
Jackson’s tricky until Lydia taps her foot — Stiles doing his best to ignore how every tap sounds like some sort of Morse code delivering the message humour the boy — and then sits there idly flicking it at random intervals.
Isaac looks particularly bored when he accepts his and then winds his scarf over it, while Boyd holds him with an unamused stare that promises loss of limb until Erica takes over and loops it about his neck with a cackle.
As for Derek, well. He hasn’t given Stiles any trouble for a long while, but he can still remember the look on the man’s face the last time they did something without him and isn't eager for a repeat. Instead, the sparkle that illuminates his eyes when Stiles holds up the final makeshift collar with a jingling flourish has his heart bobbing upwards in his chest, choking him on a whine when Derek tilts his head back and bares his throat as Stiles’ trembling fingers fumble with the knot. When he looks up, the sparkle has turned to the dark glitter that comes with accepting a challenge.
The improvement to his well-being is palpable. No more snickered assumptions of incontinence, no more bruises from startled leaps into inanimate objects, and even though hearing Jackson’s bell approach during lacrosse practice does nothing to protect him, he can at least brace himself in preparation for when the guy slams him into the ground.
But it’s at home where things get weird. It starts small, like putting a glass down on the table next to the sofa only to have it end up back on the kitchen counter when he reaches for it a minute later. Or like the Pop-Tarts conspicuously disappearing from the kitchen cupboard after only just announcing to his room he feels like a snack or three. He’s sure he doesn’t imagine the low chuckle floating in from the lounge.
But then it escalates. One night he’s sitting at his computer, music only drifting from his speakers, and when he switches off to go to bed, he spins round on his chair to find his bedroom window wide open and his sheets slightly rumpled with an indentation of a head in his pillow. He half wants to indulge Derek with some well-deserved applause, but the other half — or maybe three-quarters — is acutely aware how easy it would be for a not-so-friendly creature of the night to nab him for a week's worth of Stiles sandwiches.
(He contemplates his scrawny arms… Make that three days.)
It’s the final straw two nights later when he finishes up in the shower and reaches out for a vanished towel.
“Derek,” he curses under his breath. He yanks on his fresh boxers despite the uncomfortable, soggy cling he knows he’ll be regretting later and storms back to his room. He’s expecting to see his towel draped on the back of his desk chair or laid out neatly on the roof outside his window. Instead, a blur pounces from behind his door, launching him backwards onto his bed, and it feels a bit like Tigger bowling over Winnie the Pooh. His head certainly feels stuffed with fluff with the way the room spins.
Derek’s grinning down at him, a smile Stiles knows his wolf is in control of, all proud and preening for successfully stalking his prey as a pleased rumble vibrates in his chest. He's so close there’s a dull, fading chill where the bell is resting, silently, in the hollow of Stiles’ throat.
Derek’s pleasure fades to a frown when he spies Stiles’ boxers, blotchy with damp, and Stiles yelps when he hooks his fingers beneath the waistband and remedies the problem.
The next day, Stiles confiscates every necklace because all he can hear is the suggestive jing-a-ling of a certain Alpha rutting against him. Jackson gives an amused snort when Stiles saws at his string with a pair of blunt scissors, his eyes flickering knowingly to Derek watching from the couch like a smug king lounging on his throne. Stiles wants to snip off his invasive nose.
Erica’s not so eager to give hers up, and he makes the foolish decision of trying to wrestle the choker off her. She only lets him win when Derek growls. He’s about to go sprawling backwards at the sudden give, but Derek catches him and buries his nose in Stiles’ neck as his bell makes a muffled tink when it gets pressed between them.
He decides Derek can keep his.