Warning: This fanfiction contains sexual themes, nudity, coarse language, and sexual intercourse. Reader discretion is advised.
--
The evening sun casts a warm glow over the city, painting the sky with hues of orange and pink. Shido Itsuka sat at the dining table, his eyes glazed over as he stared at his untouched dinner. He felt the world's weight on his shoulders, a burden that had been growing heavier with each passing day.
Kotori Itsuka, his FOSTER sister, watched him from across the table. She could see the stress etched into his features, his shoulders slumped, and the faint lines of worry that marred his usually cheerful expression. It pained her to see him like this, knowing that he was carrying so much on his own.
"Shido," Kotori said softly, breaking the silence that had settled over them. "Is everything alright?"
Shido blinked and looked up at her, forcing a small smile. "Yeah, I'm fine, Kotori. Just a lot on my mind."
Kotori frowned, not convinced by his answer. She knew him better than that. "Shido, you can't fool me. I can see that something's bothering you. Please, tell me what's going on."
Shido sighed, running a hand through his hair. "It's just... everything. The Spirits, school, trying to keep everyone safe. It's a lot to handle."
Kotori got up from her seat and walked over to him, placing a gentle hand on his shoulder. "You don't have to do it all alone, you know. I'm here for you."
He looked up at her, his eyes filled with gratitude. "I know, Kotori. But sometimes it feels like there's no escape from it all."
She nodded, understanding his feelings all too well. "Is there anything I can do to help? Anything at all?"
Shido hesitated for a moment before speaking, his voice barely above a whisper. "I could use a daily release of dopamine. Something to help me feel better, even if it's just for a little while."
Kotori's eyes widened slightly as she processed his words. She knew that dopamine was often associated with pleasure and reward, and she realized what he might be implying. Her heart raced as she considered the implications, but she pushed her feelings aside, focusing on Shido's well-being.
"Shido," she said softly, her voice trembling slightly. "If that's what you need, then I'll do whatever I can to help you."
He looked at her, surprise and relief mingling in his expression. "Are you sure, Kotori? I don't want to make things weird between us."
She smiled gently, her resolve firm. "You're my brother, Shido. I care about you more than anything. If this is what you need to feel better, then I'll do it. No matter what."
Shido reached out and took her hand, squeezing it gently. "Thank you, Kotori. I don't know what I'd do without you."
--
That night, after everyone else had gone to bed, Kotori knocked softly on Shido's bedroom door. When he opened it, she stepped inside, her heart pounding in her chest. She had changed into a simple nightgown, the soft fabric clinging to her slender frame and highlighting her figure. Her breasts, an impressive G-cup, strained against the fabric, her curves more pronounced in the dim light of the room.
Shido's eyes widened as he took in her appearance, his breath catching in his throat. "Kotori..."
She walked over to him, her eyes filled with determination. "Shido, I want to help you. Please, let me do this."
He swallowed hard, his emotions swirling within him. "Kotori, are you sure about this? I don't want to hurt you."
She placed a finger against his lips, silencing him. "I trust you, Shido. And I want to make you feel better. Please, let me do this for you."
Shido nodded, his heart aching with both desire and guilt. He knew this was crossing a line, but the need for release was overwhelming. He gently cupped her face in his hands, leaning in to kiss her softly.
Kotori responded eagerly, her arms wrapping around his neck as she pressed herself against him. The kiss deepened, their tongues intertwining as they lost themselves in the moment. Shido's hands roamed her body, exploring the curves he had never allowed himself to touch before.
He traced the outline of her breasts through the thin fabric of her nightgown, feeling the warmth of her skin beneath his fingers. Kotori moaned softly against his lips, her body arching into his touch.
"Shido," she whispered breathlessly, "I've wanted this for so long. Please, don't stop."
His hands moved to the hem of her nightgown, slowly lifting it up and over her head. She stood before him, her body bare and vulnerable. Shido's eyes roamed over her, taking in every detail of her flawless skin, her full breasts, and the soft curve of her hips.
"You're beautiful, Kotori," he murmured, his voice filled with awe. "Absolutely stunning."
She blushed deeply, her eyes locking onto his. "Shido, I want to make you feel good. Let me take care of you."
He nodded, his breath coming in short, heavy gasps as she gently pushed him back onto the bed. Kotori climbed on top of him, straddling his hips as she leaned down to kiss him again. Her breasts pressed against his chest, their warmth and softness sending shivers of pleasure down his spine.
Kotori began to move her hips, grinding against him through the fabric of his pants. Shido groaned, his hands gripping her hips as he guided her movements. She could feel him growing hard beneath her, the friction adding to her arousal.
"God, Kotori," he panted, "you feel so good."
She smiled, her eyes filled with desire. "I want you, Shido. I want to make you feel amazing."
She reached down, her fingers deftly undoing the button and zipper of his pants. She tugged them down along with his underwear, freeing his erection. Shido gasped as she wrapped her hand around him, stroking him slowly.
"Does this feel good, Shido?" she asked, her voice low and seductive.
"Yes," he groaned, "it feels incredible."
Kotori continued to stroke him, her movements slow and deliberate. She watched his face, delighting in the way his eyes fluttered shut and his mouth fell open in a silent moan. She could feel herself growing wetter with each passing second, her desire for him reaching a fever pitch.
"Shido," she murmured, "I want to taste you."
His eyes snapped open, filled with a mix of surprise and longing. "Kotori, are you sure?"
She nodded, her expression serious. "I've never been more sure of anything in my life."
Kotori slid down his body, positioning herself between his legs. She took a moment to admire him, her eyes filled with hunger. She leaned forward, her breath warm against his skin as she began to lick the length of his shaft. Shido moaned, his hands tangling in her hair as she took him into her mouth.
She started slow, her tongue swirling around the tip before she took him deeper, her lips forming a tight seal around him. Shido's hips bucked involuntarily, a guttural groan escaping his lips as Kotori worked her magic. She bobbed her head, taking him deeper with each movement, her hands massaging his thighs.
"Fuck, Kotori," he gasped, "your mouth feels amazing."
She moaned in response, the vibrations adding to his pleasure. Kotori picked up the pace, her hand stroking the base of his shaft as she took him deeper into her mouth. Shido's moans grew louder, his body trembling with the intensity of his arousal.
"I'm close, Kotori," he panted, "I'm going to cum."
Kotori didn't slow down, her movements becoming more urgent as she brought him to the edge. With a final thrust of his hips, Shido came, his release filling her mouth. She swallowed eagerly, her eyes locked onto his as she licked him clean.
"You're amazing, Kotori," he breathed, his body still shuddering from the intensity of his orgasm.
She smiled, her lips glistening. "I'm not done with you yet, Shido."
Kotori stood up, her breasts swaying with the movement. She climbed onto the bed, positioning herself over him. Shido's eyes widened as she pressed her breasts around his still-hard erection, her soft flesh enveloping him completely.
"Does this feel good, Shido?" she asked, her voice low and seductive.
"Yes," he groaned, "it feels incredible."
Kotori began to move her breasts, sliding them up and down his length. The sensation was unlike anything Shido had ever felt before, the soft warmth of her skin driving him wild. He reached up to squeeze her breasts, his fingers digging into her soft flesh as she continued her movements.
"Fuck, Kotori," he panted, "your tits feel so good."
She smiled, her eyes filled with desire. "I want you to cum again, Shido. I want to feel you explode."
Her words sent a shiver down his spine, his arousal reaching a fever pitch. Kotori increased the pace, her breasts moving faster and faster as she brought him to the edge once more. With a final thrust of his hips, Shido came again, his release coating her breasts.
Kotori moaned, her fingers spreading his release over her skin. "You're so good for me, Shido. But I want more. I need to feel you inside me."
Shido's breath hitched as he watched her, his desire for her growing even stronger. "Kotori, are you sure?"
She nodded, her eyes filled with determination and lust. "I've never been more sure of anything in my life, Shido. Please, take me."
Shido sat up, pulling her close and capturing her lips in a deep, passionate kiss. He could taste himself on her, the mingling of their desires making his head spin. He gently laid her back on the bed, positioning himself between her legs. Kotori spread her thighs wider, her body trembling with anticipation.
Shido lined himself up with her entrance, pausing for a moment to meet her gaze. "If you want to stop, just say the word."
Kotori shook her head, her voice steady despite her arousal. "I want this, Shido. I want you."
With a slow, careful movement, Shido pushed into her, groaning at the feeling of her tight, wet heat enveloping him. Kotori gasped, her fingers digging into his shoulders as he filled her completely.
"Shido," she moaned, "you feel so good inside me."
He began to move, his thrusts slow and deliberate at first, giving them both time to adjust to the sensation. Kotori wrapped her legs around his waist, urging him deeper. Shido increased the pace, his hips snapping forward as he drove into her, their bodies moving in perfect harmony.
"Harder, Shido," Kotori pleaded, her voice filled with need. "I need you harder."
Shido complied, his movements becoming more urgent as he pounded into her. The sound of their bodies coming together filled the room, mixed with their moans and gasps
of pleasure. Kotori's nails raked down his back, the slight pain only adding to his pleasure.
"Fuck, Kotori," he groaned, "you're so tight. You feel incredible."
"Shido," she gasped, "I'm so close. Don't stop."
He could feel her tightening around him, her body trembling as she neared her release. Shido reached between them, his fingers finding her clit and rubbing it in time with his thrusts. Kotori cried out, her body arching off the bed as her orgasm crashed over her.
"Shido!" she screamed, her inner walls clenching around him.
The sensation pushed Shido over the edge, his release hitting him with the force of a tidal wave. He thrust into her one last time, spilling himself deep inside her as he moaned her name.
They collapsed together, their bodies slick with sweat and trembling from the intensity of their shared pleasure. Shido gently pulled out of her, rolling to the side and pulling Kotori into his arms. They lay there, wrapped in each other's embrace, their breaths slowly returning to normal.
"Thank you, Kotori," Shido whispered, his voice filled with emotion. "You have no idea how much this means to me."
Kotori smiled, her eyes filled with love and contentment. "I'll always be here for you, Shido. No matter what."
In the days that followed, Shido and Kotori found a new sense of balance in their relationship. The daily release of dopamine that Kotori provided became a source of comfort and strength for Shido, helping him to face the challenges of each day with renewed vigour.
Their bond grew stronger, built on a foundation of trust and unconditional love. And though they knew that their actions would never be understood by others, they found solace in each other, knowing that they would always be there to support and care for one another.
In the end, it was not just the release of dopamine that brought Shido peace, but the knowledge that he was never truly alone. With Kotori by his side, he knew that he could face anything the world threw at him and that together, they could overcome any obstacle.