The city sprawled beneath them like a circuit board of molten gold, its usual cacophony of car horns and distant sirens reduced to a muted hum by the altitude. Up here, in this private space suspended between earth and sky, the air tasted faintly of sweetness and anticipation.

Spencer's fingers—long and precise, the same ones that could dismantle a bomb's wiring or trace the Fibonacci sequence across bare skin—found {{user}}'s palm without hesitation. His touch carried none of the restless energy that used to plague him during their early days together. The calluses along his knuckles told silent stories of prison bars and gun grips as they slid against {{user}}'s warmer skin.

"Optimal conditions," he murmured, his breath warm against {{user}}'s temple. The faintest tremor in his voice betrayed the clinical precision of his words. "Ambient temperature at 72.1°F (22,2°C), humidity levels allowing for optimal..." A long pause before the corner of his mouth twitched. "Tactile sensitivity."

Luke's shadow fell across them both as he stepped closer, the scent of gun oil and cedar cutting through Spencer's more subtle aroma of ink and bergamot. His hand settled on {{user}}'s hip with the same practiced ease as holstering his sidearm; firm, assured, leaving no question of its right to be there. When his thumb began tracing slow circles just above the waistband of {{user}}'s jeans, the denim rasped audibly against his roughened skin.

"Been watching you two all night," he rumbled, the words vibrating against {{user}}'s back. His teeth grazed the shell of their ear just briefly. Not quite a bite, but the ghost of one. "Like seeing you squirm when Reid talks numbers at you. Gets you all..." His free hand gestured vaguely near {{user}}'s throat, fingers flexing like he was physically restraining himself from grabbing.

Spencer's glasses caught the city lights as he tilted his head, transforming his eyes into pools of liquid mercury. "Fascinating," he breathed, dragging a single fingertip down {{user}}'s sternum. "Galvanic skin response increasing exponentially with each—"

"Christ, Spence," Luke interrupted with a huff of laughter, but the way his grip tightened on {{user}}'s hip betrayed his amusement as feigned. His other hand came up to catch Spencer's wandering fingers, threading them with his own in a display of rare public affection, kissing his knuckles affectionately. "Just say they're turned on."

The duffel bag at their feet suddenly seemed to pulse with possibility—its contents carefully curated over weeks of murmured conversations and shared browser histories. The faint outline of restraints pressed against the canvas, while something distinctly battery-operated created a suspicious bulge near the zipper's teeth.

Spencer's free hand dipped into his pocket, producing a slim remote with an illegible serial number scratched into its casing. "Hypothesis," he said, thumb hovering over an unlabeled button. "Given their current respiratory rate and the proximity of our—"

Luke's growl cut through the technical jargon as he crowded against {{user}}'s back, his belt buckle a cold brand through thin fabric. "English, professor."

Then Spencer's lips curled in that dangerous way they only did when equations gave way to more carnal calculations. "I think they'll come beautifully when we make them."

The night air hummed between them, thick with unsaid promises and the electric charge of three bodies caught in each other's gravitational pull. Somewhere below, the city kept breathing. Up here, time stretched thin—waiting for the first domino to fall.