Beast Gacha System: All Mine-Chapter 80: Forbidden

Arkai had led a straight life.

He would swear it on his mother’s grave, and meant it, that he was an honorable and principled man.

While other alphas reveled in their baser instincts, he had mastered his. He had restrained his own beastly desire, the primal hunger, the territorial rage, the raw, possessive lust of his lineage more times than the average beast had even felt such urges.

Of course, there was a reason he had the right to say this about himself.

The living, breathing proof was named Rinne.

"Step-Brother... I’m sorry..."

His mother, Belinda Zayra, a woman of the same fierce stock as Anton’s mother, her sister Bertha, had been strength incarnate. Until a plague took her. His father, August Dawnoro, wore his grief like a second pelt for a decade before remarrying a widowed female wolf named Ines.

Ines brought a daughter from her first union.

Sienna.

"Step-Brother... I love you..."

Female beasts were not like human women. Upon maturity, their bodies initiated a cycle called... heat. For most, it was manageable. Either strictly regulated with potent alchemical suppressants if unmarried, or tended to by a bonded mate if wed.

Sienna was the Snowflower of the North, a creature of such beauty she was the dream of every ambitious alpha. But her heat, when it first struck at eighteen, was a catastrophe.

The strongest suppressants failed.

And every single time, without fail, the overwhelming, scent-drenched tide of her need would drive her to one man.

Arkai.

Even now, no memory was so shameful more than those youthful days. The monthly, inescapable scent-triggered rut, forced upon him by the unmanaged heat of his own sister, when he never even wanted it.

He remembered locking himself in his bathroom, submerging his tormented body in ice-choked wooden tubs until his skin turned blue, teeth chattering against the animal fury in his blood.

And on the other side of the door, her voice, whispering his name, over and over, a siren song he was biologically programmed to answer.

Then, when dawn arrived, the heat would pass. And Sienna, the Snowflower, would re-bloom. She would look at him with sisterly eyes, pour his tea, ask about his training. As if the previous night’s whispered pleas and the scent of familial violation had never happened.

But something eventually, definitely happened.

Their father, August, walked in at the worst possible moment. He saw Arkai in a scene designed for maximum misunderstanding. August saw him physically forcing Sienna down onto his own bed, using cords to bind her wrists to the bedpost.

At the time, Arkai was furious. Panicked. There was no lust in him. He was trying to restrain her, to immobilize her long enough for him to flee into the frozen woods and outrun the chemical pull of her heat.

From any angle, it looked like a violent assault.

That night, August did not ask questions. He struck his son across the face so hard Arkai forgot where he was when the floor embraced him.

The next blur of his father’s judgment was swift and brutal. August locked him into a lightless dungeon cell for three whole months. Every attempt to explain, to defend his actions, was met with the lash or a closed fist.

The only silver lining, if it could be called that, was the new policy that followed his release. Whenever Sienna’s heat came upon her, she was now the one locked away, securely confined to her chambers, forbidden from seeking anyone out. 𝑓𝘳𝘦𝑒𝑤𝑒𝘣𝘯ℴ𝘷𝘦𝓁.𝑐𝑜𝑚

Arkai believed, later, that his father had pieced together the ugly truth. But the old wolf never offered an apology. Not a word of remorse, even on his deathbed.

And after August died, the old terror returned.

With the patriarch gone, the strict confinement relaxed. Sienna’s heat became, once again, her own, and therefore, Arkai’s problem.

He became a man obsessed with a cure. He scoured the continent for physicians, alchemists, any rumor of a potion or charm that could leash her biology. But after only a few failed trials, Sienna refused to continue. She claimed it was hopeless.

Sometimes, Arkai wondered if she truly couldn’t control her desire for him during those times. Sometimes, Arkai wondered what would happen if he couldn’t control his own beastly desires.

Then, the irreversible happened.

Sienna’s recklessness, her refusal to be properly secured, her wandering during a cycle, led to the next catastrophe.

Rinne was born. Sienna claimed she didn’t remember the father. That was a lie. She knew. She simply refused to admit she had been taken advantage of, violated in her vulnerable state.

But Arkai found out.

The father was his own former beta, his right hand. Arkai exiled the man from his territory and his life the same day he learned the truth.

The childbirth broke something in Sienna. She withered away. Whenever Arkai was near, her eyes would fix on him, burning with blame. On her deathbed, she finally spat the truth at him, "If only you had loved me back..."

In that moment, any lingering doubt vanished. Arkai knew with absolute certainty that his stepsister had never, not for a single day, seen him as her brother.

Everything that followed was as known. He adopted the boy, giving him his name and his legacy, making Rinne his sole heir.

When curious lords asked why the formidable Black Wolf King showed no interest in taking a Luna, he had his polished answers. Early on, it was ’duty before pleasure.’ Later, once Rinne was in his arms, it became, ’I already have my heir. My pack is my family.’

The truth was, he could not fathom subjecting any woman to the reality of his home. To a life where her husband’s own sister would come scent-drunk and desperate to their door every month.

Where would he bury his face then?

That was why Arkai believed that he was immune to taboo. His life had been spent resisting the forbidden. He had built his honor as a fortress against it.

Only to storm his own walls. Only to fall for his own former niece-by-marriage—and no less a woman bound to his own nephew, and then to a dragon.

"Uncle-in-law," she breathed. "Let’s hide. We mustn’t get caught..."

Heavens, damned be.

In the end, despite every princely pretense, every kingly restraint... he was, at his core, a beast.

"Cece," Arkai warned. He used his body to press her more firmly against the cold stone, caging her in. "You should stop this game. Now."

Cecilia merely hummed, a vibration he felt through the scant space between them. "Mmm, such a stern, principled man..." She tilted her head, a coy look in her eyes. "But I know what kind of beast you truly are."

Arkai’s eyes narrowed.

"You," she whispered, her gaze holding his, "enjoy these forbidden thrills more than anything else. Don’t you?"

Perhaps she was right. Perhaps a lifetime of monstrous restraint had simply created a monster of a different kind. One that now reveled in the very taboos he’d once fled. A broken dam.

Or—

He had simply found someone for whom he would willingly break every rule, shatter every principle, and embrace the beast.

If it meant she was his.