The heavy stone door of the cave scraped shut, sealing them in absolute darkness and silence.

Catherine dropped Amon's hand and let out a massive, shuddering breath. Her heart was still hammering against her ribs from the confrontation. She turned around, opening her mouth to explain that she only said those words to stop a bloodbath.

She never got the chance.

Amon moved faster than her eyes could track. He stepped into her space, his massive frame driving her backward until her spine hit the cold, rough stone wall.

He slammed both hands flat against the rock on either side of her head, caging her in.

The heat radiating from his body was scorching. His chest he heave, his rapid breaths ghosting over her forehead. In the dim light of the cave, his golden, slitted eyes burned with a terrifying, desperate fire.

"What you said out there..." Amon's voice was a broken, gravelly rasp. His jaw ticked violently. "Was it true?"

Catherine stared up at him. She was trapped. The sheer physical dominance of his body pressed against hers made her breath catch in her throat.

She looked into his eyes and saw the raw, bleeding vulnerability hiding beneath the predator. He was begging her for it to be true. If she told him it was a lie, it would destroy him.

Catherine swallowed hard. Her hands trembled as she raised them, resting her palms flat against his burning chest.

"Yes," she whispered. "It's true."

The word was a spark dropped into a powder keg.

A guttural groan ripped from Amon's throat. He ducked his head and crushed his mouth against hers.

There was no hesitation. No gentleness. It was a kiss of absolute, starving desperation. His lips were hot and demanding, forcing her mouth open. His tongue swept inside, tasting of wildness and a strange, intoxicating coldness that contrasted with his burning skin.

Catherine's knees went weak. The world spun out of control. She grabbed fistfuls of his hair, holding on for dear life as he devoured her.

Then, everything went wrong.

Amon's body violently convulsed against hers.

He tore his mouth away, throwing his head back as a horrific, agonizing scream tore from his lungs. It sounded like a beast being burned alive.

Catherine stumbled forward as Amon staggered back. "Amon? What's wrong? !"

He didn't answer. He couldn't.

A shockwave of pure, black energy exploded from his body. The temperature in the cave plummeted instantly. A layer of black frost crawled rapidly up the stone walls, freezing the moisture in the air.

Amon fell to his knees, clutching his head. The veins on his neck bulged, pulsing with thick, black energy. The human skin on his face began to tear, revealing thick, jagged black scales underneath. His golden eyes flickered wildly between round human pupils and the lethal slits of a snake.

His rut had triggered. The emotional extreme of her acceptance had shattered the dam holding back his unstable, violent energy.

"Amon!" Catherine screamed, terrified. She rushed forward, reaching out to grab his shoulders.

"DON'T TOUCH ME!" Amon roared.

He threw his arm out. The back of his hand struck her shoulder, sending her flying backward. Catherine hit the fur-covered stone bed hard, the breath knocked out of her.

She gasped, clutching her shoulder, staring at him in horror.

Amon was on all fours, his fingers digging into the solid rock floor until his nails cracked and bled. He was fighting a losing battle against the monster inside him. The black energy storm whipped around the cave, shattering the clay pots and sending shards of pottery flying like shrapnel.

His spine arched unnaturally. The sickening sound of bones breaking and reforming echoed in the cave. He was being forced into his full beast form.

He turned his head, his eyes bloodshot and wild, locking onto Catherine. The predator inside him wanted to tear her apart, to consume her entirely.

"Run," Amon ground out, his teeth cracking under the pressure of his clenched jaw. "Get out. I will kill you."

Catherine couldn't move. She was paralyzed by the sheer terror of the energy storm and the monster he was becoming.

Seeing that she wasn't running, Amon let out a sob of pure despair.

He raised his right hand. His fingers had completely morphed into long, razor-sharp black talons.

Without a second of hesitation, Amon drove his own claws deep into his left thigh.

Blood sprayed across the stone floor. Amon threw his head back and screamed, using the excruciating, blinding physical pain to force his human consciousness to stay awake for just one more second.

"RUN!" he roared, blood pouring down his leg.

The metallic stench of Amon's blood hit Catherine like a physical blow.

She stared at the crimson pool spreading rapidly across the gray stone floor. Her heart hammered against her ribs, a frantic, painful rhythm. Every survival instinct in her modern brain screamed at her to run, to get as far away from this terrifying, bleeding monster as possible.

She scrambled backward on the bed. Her hand brushed against something sharp. It was a jagged shard of pottery from one of the shattered bowls.

Catherine grabbed it. Her knuckles turned white as she gripped the sharp edge, holding it out in front of her like a weapon. Her whole body shook violently.

Amon saw the shard in her hand.

He was still kneeling in his own blood, his claws buried deep in his thigh. He was panting heavily, his breath coming out in white clouds of frost. When his golden, slitted eyes locked onto the makeshift weapon in her trembling hands, a look of profound, devastating sorrow washed over his face.

"Yes," Amon gasped, his voice barely a whisper over the howling of the black energy storm. "If I lose control... if I lunge at you... use it. Pierce my throat."

The words pierced Catherine's heart sharper than any physical blade.

She looked at him. He was a seven-star predator. He could level a forest. Yet here he was, mutilating his own body, begging her to kill him just to ensure she stayed safe.

The terror that had paralyzed her suddenly shattered, replaced by an overwhelming, suffocating wave of heartbreak.

Clatter.

Catherine opened her hand. The sharp piece of pottery hit the stone floor.

"I'm not leaving," Catherine said. Her voice stopped shaking. "And I'm not hurting you."

She slid off the fur bed. The black wind whipped her hair around her face, the razor-sharp energy leaving tiny, stinging cuts on her bare arms. She ignored the pain. She ignored the terrifying beast he was becoming.

She walked straight toward him.

"No! Stay back!" Amon panicked, trying to drag himself backward, but the severe wound in his leg made him collapse onto his side.

Catherine dropped to her knees right in the middle of the blood and frost. She reached out and threw her arms around his massive, trembling neck, pressing her body tightly against his freezing, scale-covered chest.

"You have to tell me what to do!" Catherine yelled over the storm, burying her face in the crook of his neck. "Is this the 'resilience' the system meant? I'm not leaving you to die! How do I help you? !"

The moment her soft, warm skin made full contact with his, the violent black storm in the cave stuttered. The pure, soothing energy radiating from her Highly Compatible body acted like a heavy blanket thrown over a raging fire.

Amon let out a long, shuddering breath. The agonizing pain in his mind dulled for a fraction of a second.

But the physical contact triggered something far more dangerous.

The biological imperative of his rut-the absolute, overwhelming need to mate and claim-obliterated his last shred of human restraint.

With a guttural roar, Amon flipped them over, pinning Catherine flat against the hard stone floor.

His hands, rough and desperate, grabbed the hem of her black t-shirt and ripped it down the middle. The fabric tore like wet paper.

Catherine gasped, a spike of fear hitting her as his heavy, burning body pressed her down. She tried to push against his shoulders, but it was like trying to move a mountain.

Amon's mouth crashed down on her neck. He bit down, not hard enough to break the skin, but hard enough to leave a dark, bruising mark. His kisses were frantic, wild, consuming her.

Below his waist, his legs had completely vanished, replaced by the thick, muscular coils of the giant black snake. The heavy, freezing scales wrapped tightly around Catherine's legs, locking her in place.

The sheer size of him, the crushing weight, and the aggressive invasion of his touch sent a sharp jolt of pain through her.

"Amon... it hurts," Catherine cried out, tears springing to her eyes.

The sound of her pain pierced through the red haze of his rut.

Amon froze. He raised his head. His chest heaved as he looked down at her. He saw the tears in her eyes, the fear in her face. The monster inside him fought violently against the man who loved her.

He squeezed his eyes shut, his entire body shaking as he tried to pull himself away from her. "Catherine... push me away... last chance..."

Catherine looked at his tortured face. She saw the blood dripping from his leg, the black scales fighting to consume him.

She reached up, tangling her fingers in his sweat-soaked black hair, and pulled his face down to hers.

"I choose you," she whispered fiercely against his lips. "Claim me."

The moment Catherine spoke those words, the final barrier broke.

With a low, rumbling growl that vibrated straight through Catherine's chest, Amon took her. The physical connection was a violent, overwhelming collision of two entirely different species.

Catherine let out a sharp cry, her fingernails digging deep into the hard muscle of Amon's back.

Instantly, an invisible, massive shockwave of energy exploded from the point where their bodies met. It blasted outward, blowing the heavy stone door of the cave open a fraction of an inch.

Amon threw his head back and let out a deafening, triumphant roar.

The chaotic, destructive black storm that had been tearing the cave apart suddenly reversed. It funneled into a tight vortex and slammed back into Amon's chest.

At the exact same moment, a searing, burning heat flared on the back of Catherine's neck. It felt like a branding iron being pressed into her skin. She gasped, arching her back.

On Amon's left collarbone, a complex, tribal tattoo of a coiled black snake began to materialize, glowing with a blinding silver light.

Simultaneously, a tiny, identical black snake mark burned itself permanently into the skin at the nape of Catherine's neck.

The Beast Mark. The absolute, one-way contract of life and death was forged.

With the bond complete, the bottleneck that had trapped Amon's power for years shattered. The energy inside him underwent a terrifying, exponential mutation.

A pillar of pure, liquid silver light erupted from his body, illuminating the dark cave like a second sun. This was the light of a seven-star evolution.

The massive, self-inflicted wound on his thigh began to knit together. Muscle, tissue, and skin regenerated at a visible, horrifying speed until there wasn't even a scar left behind.

But the biological drive of the rut didn't stop with the upgrade. The influx of new, massive power only made Amon more relentless.

Catherine was tossed in a violent storm of pleasure and pain. She had no concept of time. The snake shifter's stamina was inhuman. She clung to his broad shoulders, her voice giving out completely as she was pushed past every physical limit her human body possessed.

Finally, after one last, earth-shattering surge of energy, the world went black. Catherine's eyes rolled back, and she passed out cold, her head falling limply against the furs.

When she slowly drifted back to consciousness, the cave was warm and quiet.

Her entire body felt like it had been run over by a steamroller. Every muscle ached with a deep, throbbing soreness. She tried to shift her weight and immediately hissed in pain.

"Don't move."

Amon's voice was incredibly soft, a stark contrast to the monster he had been hours ago.

Catherine forced her eyes open. Amon was kneeling beside the bed. He was fully in his human form, looking immaculate. The dark circles under his eyes were gone. His skin had a healthy, powerful glow.

He was holding a piece of soft, white fur that had been soaked in warm water. He gently, meticulously wiped the sweat and dried blood from her arms and chest.

When he finished, he pulled a thick, dry fur blanket up to her chin, tucking her in securely.

He looked down at her, his golden eyes entirely soft, brimming with a terrifying depth of devotion. He reached out and gently brushed a strand of hair away from her neck, his thumb lightly tracing the new black mark on her skin.

"You are mine now," Amon whispered, leaning down to press a reverent kiss over the mark. "Forever."

He stood up and walked over to the fire pit. A piece of fresh, high-grade monster meat was roasting on a stick, the savory fat dripping into the flames.

He tore off a tender, bite-sized piece, carefully testing the heat against the rough skin of his forearm to ensure it wouldn't burn her, and walked back to the bed.

"Eat," Amon coaxed, holding the meat to her lips. His jaw was relaxed, a small, almost goofy smile playing on his lips.

Catherine glared at him. He looked so refreshed and smug while she felt like a broken doll.

She reached out with a trembling arm, grabbed the small fur pillow next to her head, and weakly threw it at his face.

The pillow bounced off Amon's nose. He didn't even blink. His smile just grew wider.

He caught the pillow, tossed it aside, and offered the meat again. "Eat. You need your strength. Then, I'll take you to the spring to wash."