[Auxiliary Chapter – A Night of Submission]
The penthouse bedroom was bathed in the warm glow of dimmed lights, casting flickering shadows along the walls. The only sound was Isa's unsteady breathing as she knelt before Natasha, her body bare except for the silk choker around her neck. The air between them was thick with tension, the kind that sent shivers down Isa's spine and made her thighs clench together involuntarily.
Above her, Natasha Romanoff sat on the edge of the bed, legs crossed, exuding effortless dominance. The red satin robe she wore was loosely tied, offering Isa teasing glimpses of her toned body beneath. She ran a slow, deliberate hand through her fiery locks, her sharp green eyes never leaving Isa's trembling form.
"You've been testing me, haven't you, зайка?" Natasha's voice was a low, sultry purr, her Russian accent thicker than usual.
Isa swallowed hard. She had always been in control, in every aspect of her life—her business, her money, her intelligence. But Natasha was different. Natasha unraveled something inside her, something desperate and needy.
"I—I didn't mean to," Isa stammered, lowering her gaze.
A firm hand grasped her chin, tilting her head up so she was forced to meet Natasha's piercing gaze. The redhead's lips curled into a knowing smirk.
"Shhh." Natasha's thumb brushed over Isa's lower lip, her touch feather-light yet possessive. "You know exactly what you were doing."
Isa whimpered softly, feeling Natasha's fingers tighten slightly.
"Say it," Natasha ordered, her voice leaving no room for defiance.
Isa's breath hitched. She knew what Natasha wanted to hear, but saying it aloud made her face burn with a mix of embarrassment and desire.
"Mommy," she whispered, her voice barely above a breath. "Please."
Natasha's smirk widened. "Good girl," she praised, her fingers trailing down Isa's jaw, along the curve of her neck, making her shudder. "But begging once isn't enough. You can do better than that."
Isa's lips parted, her body trembling under Natasha's touch. She knew she was being toyed with, drawn out, made to submit in the most delicious way. And she loved it.
"Please, Mommy," she whimpered again, her voice softer, more desperate. "I need you. I— I can't take it anymore."
A satisfied chuckle escaped Natasha's lips. "That's more like it."
With slow, predatory grace, she stood up, towering over Isa before gently pushing her back onto the bed. Isa gasped as her wrists were pinned above her head with one hand, her body completely at Natasha's mercy.
"You act so strong during the day," Natasha mused, leaning down until her lips were just a breath away from Isa's. "So untouchable, so confident. But look at you now."
Isa whimpered, her heart pounding against her ribs.
"You need someone to take control, don't you, зайка?" Natasha's voice was velvet-soft, but there was steel underneath. "You need your Mommy to take care of you."
Isa's breath hitched, her thighs pressing together instinctively.
"Say it."
"Y-Yes, Mommy," Isa admitted, her voice breaking with need.
"Good girl."
Natasha's lips finally crashed against hers—fierce, demanding, utterly possessive. Isa melted into the kiss, her body arching as Natasha deepened it, claiming her with every stroke of her tongue.
When Natasha pulled away, Isa was left panting, her lips swollen and aching for more.
"You're mine," Natasha murmured, her hand sliding down Isa's body, teasing, tormenting, drawing out every whimper and moan.
Isa had never felt more wanted. More owned. More loved.
And tonight, she was going to be reminded exactly who she belonged to.
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[Auxiliary Chapter – Possessive Punishment]
The night had started as a simple business party—an elegant event where power, influence, and wealth mingled. Isa had attended with Natasha by her side, the assassin looking absolutely stunning in a sleek black dress that hugged her body perfectly. But Isa, being the little tease that she was, had decided to push Natasha's limits.
She had been subtle at first—brushing her fingers over the hands of businesswomen while laughing softly at their jokes, leaning just a bit too close during conversations. Natasha had remained composed, her expression unreadable, but Isa knew better. She saw the way Natasha's jaw clenched, the way her green eyes darkened with something dangerously possessive.
The final straw had been when Isa let a particularly attractive woman tuck a strand of her hair behind her ear, their fingers lingering just a little too long.
That was when Natasha had whispered in Isa's ear, her voice cold and sharp, "You're going to regret that, зайка."
Now, back in Isa's penthouse, she was pinned against the bed, completely naked, her wrists bound with silky red restraints that Natasha had pulled from her purse as if she had planned this all along.
"Did you enjoy yourself, little one?" Natasha murmured, sitting beside Isa, one hand tracing slow circles over her bare thigh.
Isa bit her lip, her heart pounding.
"It was just a little fun," she whispered, her voice holding the tiniest hint of defiance.
Natasha's grip tightened. "Fun?" She leaned down, lips barely brushing Isa's ear. "Teasing me in public? Flirting with others when you know who you belong to?"
Isa shivered. She loved seeing Natasha like this—her control, her possessiveness. It sent a thrill straight through her, making her body burn with need.
"Mommy," Isa whimpered, tugging against the restraints. "I'm sorry."
Natasha's smirk was dangerous. "Oh, you will be."
With one swift motion, she flipped Isa onto her stomach, her soft skin exposed to the cool air. A sharp smack landed on her ass, making Isa gasp.
"Count for me," Natasha ordered.
Isa swallowed hard. "O-One."
Another sharp smack.
"Two."
The pattern continued, each slap sending a mixture of pain and pleasure coursing through Isa's body. By the time Natasha reached ten, Isa was trembling, her breath ragged.
Natasha leaned down, pressing a kiss against the reddened skin. "Look at you," she purred. "So needy. So desperate for my attention."
Isa whimpered, shifting against the restraints. "Please, Mommy."
Natasha chuckled, reaching for the bedside drawer. "I think it's time you learned your lesson."
Isa barely had time to process her words before she felt something cool press against her entrance—a long, thick dildo, one she recognized all too well.
"Since you wanted to act like a little brat tonight, I'm going to remind you exactly who you belong to," Natasha murmured, slowly pushing it inside.
Isa moaned, her body arching against the restraints, completely at Natasha's mercy.
"You're mine, Isabella," Natasha growled, her hand gripping Isa's waist firmly. "Say it."
"I-I'm yours, Mommy," Isa gasped. "Only yours."
"Good girl," Natasha purred, pressing a possessive kiss to Isa's shoulder before setting a slow, torturous rhythm.
Tonight, Isa wouldn't forget who she belonged to.