The vinegar did nothing. The lye solution just dissolved the cloth fibers, turning the blood into a brackish smear. But the gallnut powder—tannic acid—that made something happen.
Elara worked by the unstable blue pulse of the cave moss, her field loupe strapped to her eye. She’d scraped a minute sample of dried blood onto a smooth stone, mixing it with a drop of water and a pinch of the dark powder. Under magnification, the cellular debris clumped. Normal. Then she did the stupid thing, the utterly unscientific thing. Frustrated, she spat on the stone beside the mixture.
The reaction was instantaneous.
Her saliva, meeting the edge of the tannic-treated blood, caused the proteins to writhe and aggregate into tight, distinct globules. Not separation. Not dissolution. A purposeful binding. She repeated it, careful this time, using a clean sliver of wood to transfer a microscopic amount of her own saliva. Same result. A biochemical handshake that defended every database in her head.
“Impossible,” she whispered to the humming dark.
“What is?”
The voice wasn’t Lyra’s. It was a low rumble that vibrated in the hollows of her bones.
Kael filled the alcove’s entrance, his shoulders nearly brushing the mossy stone. The bioluminescent light caught the gold in his eyes, turning them into banked fires. He wasn’t in his wolf form, but the raw, animal gravity of him was the same. His gaze went past her, past the loupe on her face, and locked onto the stained linen spread on the furs beside her.
Every cell in Elara’s body tightened. She instinctively cupped a hand over the stone. “It’s nothing. An experiment.”
He took one step inside. The air pressure changed. The gentle hum of the cave seemed to deepen in pitch. “You stole from me.”
“It was discarded biological matter. That’s not theft, that’s salvage.” Her voice sounded thin, academic. Pathetic.
Another step. The scent of him—cold stone, pine, and that dark musk—rolled over her, obliterating the subtler smells of vinegar and herbs. “You’re lying. Your heart is hammering. I can smell the adrenaline sharp in your sweat. And the curiosity.” His nostrils flared. “It’s sour. Metallic. Like cut wires.”
“Get out.” She didn’t move.
He was in front of her in a blur of motion that her human eyes couldn’t track. One hand closed around her wrist, pulling her cupped hand away from the stone. His skin was searing hot. His thumb pressed against her frantic pulse. He looked down at the crude slides, the tiny, damning globules.
“What did you find?” he growled.
“A protein. One I’ve never seen. It reacts to my own enzymes. It shouldn’t.” She tried to pull her hand back. It was like tugging against iron.
“It should. It’s mine. And it recognizes you.” His other hand came up, fingers brushing a strand of hair from her cheek. The touch was shockingly gentle, at odds with the fury in his eyes. “Your science just found the proof you begged for. What does your rational mind do with that, Doctor?”
It short-circuited. That was the only answer. The data was there, on the stone. A correlation so strong it screamed causation. Her body’s response to his proximity—the heat pooling low in her belly, the sudden dryness of her mouth—was just another data set, horrifyingly consistent.
She hated it.
“It could be a contaminant. A reaction to the gallnut. My methodology is flawed.” The words tumbled out, a last defense.
“Stop.” The command was quiet, absolute. His hand left her face, sliding down to her hip. He pulled her against him. Every hard plane of his body aligned with hers. She felt the powerful rhythm of his heart, the terrifying, rigid proof of his arousal pressed against her stomach. A jolt of pure, undiluted lust shot through her, viscous and hot.
She gasped.
“See?” His mouth was at her ear, his breath scalding her skin. “Your body’s methodology is perfect.”
She shoved at his chest. It was futile. He caught her hands, pinning them behind her back with effortless strength. The motion arched her into him, and a ragged moan escaped her before she could choke it back. Humiliation burned her cheeks.
“Let me go.”
“No.” He lowered his head, his nose tracing the line of her throat. He inhaled deeply, a shudder running through his massive frame. “The moon rises tomorrow. This ends then. But your scent… it’s driving me to the edge. You, in here, picking at my blood while your own blood sings for me. It’s a special kind of torture.”
He shifted his grip, freeing one hand. It slid down over the curve of her ass, gripping hard, then moved around to the front. His palm pressed flat against her lower belly, and she jerked. His fingers slipped lower, finding the seam of her through the thin, borrowed trousers.
She went utterly still.
He cupped her. The heat of his hand was staggering. His thumb found the sensitive nub of her c**t and rubbed, once, slowly, through the fabric. A bolt of white-hot pleasure tore a choked sound from her throat. Her knees buckled. He held her up, pressed against him.
“Even here,” he whispered, his voice rough with a savage kind of triumph. “You’re soaked for me. Your cunt knows the truth. It’s the only part of you not lying to itself.”
Tears of fury and unwanted arousal pricked her eyes. She was slick, throbbing, her body arching into that clever, tormenting thumb despite the scream of her mind. He pressed harder, circling, and a wave of sensation blurred her vision. She was panting, each breath filled with his scent.
“I hate you,” she breathed, the words trembling.
“I know.” He didn’t stop his movement. “Hate me tomorrow. Tonight, just feel it.”
He kissed her. It wasn’t gentle. It was possession. A claiming. His mouth was hot and demanding, his tongue sweeping in, tasting her. She bit him. The coppery tang of his blood flooded her mouth, and instead of stopping, he groaned, deepening the kiss, feeding her his blood as his hand worked her ruthlessly through the fabric.
The dual sensations—the raw intimacy of his blood on her tongue, the relentless pressure between her legs—unraveled her. A climax, sharp and shocking, ripped through her. She cried out against his mouth, her body seizing, shaking uncontrollably in his arms.
He held her through it, swallowing her sounds, his own body rigid with strain. When the last tremor subsided, he broke the kiss, resting his forehead against hers. They were both breathing harshly.
He released her hands. She didn’t move them. She stood there, hollowed out, horrified.
He stepped back. His gold eyes were molten, his expression bleak. He looked from her shattered face to the evidence of her pleasure darkening the fabric of her trousers.
“The protein,” he said, his voice back to that dead, flat rumble. “We call it veritatis sanguis. The truth in the blood. It only reacts to a true mate. You can run every test you can imagine. The result won’t change.”
He turned and left the alcove, leaving her standing in the blue, pulsing light.
She sank to the furs, her legs useless. The stone with its damning slides sat nearby. Her body still hummed with aftershocks, a traitorous, glowing satisfaction. She wiped her mouth, his blood a faint rust-colored smear on the back of her hand.
She had her proof. It had just come at a cost her methodology had never accounted for.