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In the rebuilt world of stone, where science reigned supreme and humanity clawed its way back from petrification, Senku Ishigami and Gen Asagiri had forged something unbreakable.
It wasn't just the alliance of a scientist and a mentalist that had saved civilizations—it was the quiet, electric bond that pulsed between them like a live wire. Senku, with his sharp mind and unyielding logic, found in Gen a puzzle that never quite solved itself, a man whose illusions and truths danced in perfect harmony. Gen, the master of deception, saw in Senku a raw honesty that stripped away all pretenses, revealing a desire that burned hotter than any flame they'd kindled in their labs.
Their love had blossomed in the shadows of their grand endeavors. Stolen glances during strategy sessions turned into lingering touches under the cover of night. They desired each other with an intensity that mirrored their chemistry—explosive, precise, and utterly consuming. Senku's hands, calloused from experiments, mapped Gen's body like a new invention, while Gen's silver tongue wove spells that left Senku breathless, craving more.
It was a crisp evening in their makeshift village, the stars twinkling like scattered diamonds above the thatched roofs. The Kingdom of Science hummed with activity during the day, but at night, it was theirs. Senku had dragged Gen away from a late-night card game with the villagers, his eyes gleaming with that familiar spark of mischief. "Come on, mentalist. I've got an experiment that requires your undivided attention."
Gen smirked, his dual-toned hair catching the moonlight as he followed Senku to their private hut. "Oh? And what kind of experiment are we talking about, Senku-chan?”
Senku chuckled, low and throaty, pushing open the door.
The hut was simple—a bed of woven mats and furs, shelves lined with prototypes and notes—but it was their sanctuary. As soon as the door shut, Senku pulled Gen close, their lips crashing together in a kiss that spoke volumes. It was hungry, demanding, laced with the love that had grown from survival to something profound.
Gen's hands roamed Senku's back, fingers tracing the muscles honed from years of labor. He murmured against Senku's neck, nipping lightly. "Missed you today."
"You're the one who's been flirting with the villagers all day," Senku teased, but there was no jealousy—only affection. He backed Gen toward the bed, shedding clothes as they went. Shirts discarded, pants kicked away, until they were skin to skin, heat building like a forge.
They tumbled onto the mats, Senku pinning Gen beneath him with a grin. "Let's see how logical you can stay now." His mouth trailed down Gen's chest, eliciting soft gasps. Gen arched into the touch, his body responding instinctively to Senku's every move. Their chemistry was undeniable—each caress, each kiss, sparked reactions that built upon the last.
Senku's hands explored lower, gripping Gen's hips, then sliding to his ass. He squeezed firmly, pressing his palms against the firm flesh, and that's when he heard it—a sharp, involuntary moan from Gen, higher-pitched than usual, laced with something raw and needy. Senku paused, his scientific mind kicking in even amidst the passion.
Interesting.
He repeated the action, pressing harder, and Gen's response was immediate: a whimper, his body tensing and relaxing in waves.
"Senku..." Gen breathed, his face flushed, eyes half-lidded with desire.
Senku's curiosity piqued. As a scientist, he couldn't ignore the pattern. He shifted, rolling them so Gen was straddling him, giving him better access. His hands returned to Gen's ass, kneading, pressing. Each time, Gen's moans grew more pronounced, his hips grinding down instinctively.
Gen laughed breathlessly, trying to play it off. "What, you analyzing me like one of your rocks now?"
"Maybe," Senku replied, his voice husky. But his mind raced. Pressure, response—could it be? He'd read about kinks when he was a horny teenager discovering porn and arousal existed. The idea of impact play triggering arousal. It fit. Gen's reactions were too consistent to be coincidence. "Hold still. I want to test a theory."
Gen raised an eyebrow, intrigue mixing with lust. "A theory? During this? You're such a nerd, Senku-chan."
"Guilty." Senku's hand lifted, then came down in a light, experimental slap on Gen's right cheek. The sound echoed softly in the hut—a crisp smack—and Gen's reaction was electric. He jolted, a gasp turning into a deep moan, his cock twitching against Senku's thigh. "There it is," Senku murmured, fascinated. "You like that?"
Gen bit his lip, embarrassment flickering before desire won out. "Maybe... I don't know. Never really thought about it."
"Liar," Senku accused playfully, but his eyes softened with love. "Your body's telling the truth. Let's prove it properly." He slapped again, firmer this time, alternating sides. Each impact drew out those intoxicating sounds—whimpers, moans, pleas. Gen's skin flushed pink under the attention, and he rocked back into Senku's hands, seeking more.
"Oh god, Senku..." Gen's voice cracked, his composure shattering. The mentalist, usually so in control, was unraveling, and it was beautiful. Their love deepened in that moment—Senku's desire to understand, to please, meeting Gen's hidden vulnerabilities.
Emboldened, Senku flipped them again, positioning Gen on his hands and knees. "Tell me if it's too much," he said seriously, always the careful scientist. But Gen nodded eagerly, pushing back.
"Do it. Please."
Senku's hand descended in rhythmic slaps, building intensity. The room filled with the sounds of flesh meeting flesh, Gen's cries growing wilder. "Harder," Gen begged, his voice muffled against the furs. Senku obliged, his own arousal spiking at the sight—Gen's ass reddening, his body trembling with pleasure-pain.
They went wild then, the experiment turning into pure, unbridled passion. Senku paused only to lube his fingers and slid them into Gen, curling them while resuming the spanks. Gen screamed in ecstasy, pushing back onto Senku's hand. "Yes, yes, fuck—Senku!"
"You're mine," Senku growled, possessiveness surging. He replaced his fingers with his cock, thrusting deep in one smooth motion. Gen clawed at the mats, tears of overwhelming sensation streaking his face.
Their bodies moved in perfect sync, chemistry exploding into fireworks. Gen came first, untouched, spilling onto the furs with a guttural cry. Senku followed, burying himself deep, the slaps softening to caresses as they rode out the waves.
Collapsed together, panting, Senku pulled Gen into his arms. "Theory confirmed. You have a spanking kink."
Gen laughed weakly, nuzzling Senku's chest. "I love you, you mad scientist."
"Love you too, mentalist."
In the afterglow, they talked—about boundaries, about trying more. Their bond, already strong, grew fiercer. In a world of stone, they were the spark that ignited everything.
The discovery had changed everything. What started as a curious observation during one of their heated nights had spiraled into a core element of their intimacy. Senku, the ever-curious scientist, couldn't resist diving deeper into the "experiment," and Gen—playful, teasing Gen—reveled in being the subject.
It was a quiet night in their hut, the village asleep under a blanket of stars. Senku had prepared in advance: a small vial of homemade oil (aloe and herbs for soothing), and the leather paddle he'd crafted weeks ago—smooth on one side, textured ridges on the other for varying sensations.
Gen knelt on the bed, face down, ass up, his lithe body already trembling with anticipation. "Senku-chan," he purred, glancing back with that signature smirk. "You gonna keep me waiting all night?"
Senku stood behind him, admiring the view—Gen's pale skin, the curve of his hips, the way he arched just so. "Patience, mentalist." His voice was steady, but the bulge in his pants betrayed his own excitement.
He started slow, as always. Hands first—warm palms rubbing circles over Gen's cheeks, spreading the oil generously. The slickness made Gen sigh, relaxing into the touch. Then, without warning, Senku's right hand lifted and cracked down—sharp, open-palmed, right across the fullest part of Gen's left cheek.
Smack.
The sound was crisp, echoing in the small space. Gen's body jerked forward, a high-pitched yelp escaping his lips. "Ah—fuck!" Immediate heat bloomed, a pink handprint rising on his skin.
Senku paused, tracing the mark with his fingers. He delivered another to the right cheek—smack—symmetrical, precise. Gen moaned deeply, pushing back, his cock already hard and leaking against the furs.
"You love this," Senku observed, voice low and rough. By the tenth, Gen's ass was a warm pink, and his moans had turned into desperate whimpers. "Senku... harder, please..."
"Greedy." Senku switched to the paddle's smooth side. He tapped it lightly first, teasing, then swung—. The broader surface distributed the sting differently, a deeper thud that made Gen cry out, his back arching sharply. "Yes! Like that—"
Senku obliged, alternating: hand spanks for sharp sting, paddle for thuddy impact. He targeted different spots—sit spots where thigh met cheek, making Gen's legs kick involuntarily; the underside for maximum sensitivity. Each strike drew new sounds: gasps, sobs, broken pleas. "More... hurts so good... Senku, please—"
Gen's skin turned from pink to red, welts rising in neat patterns from the paddle's ridges. Tears pricked his eyes, not from pain alone but overwhelming pleasure—the endorphin rush, the vulnerability, the trust in Senku to push him exactly where he needed.
Senku's free hand gripped Gen's hip, steadying him. "Look at you," he murmured, awe in his tone. "Taking it so well." Between spanks, he dipped fingers into Gen's hole, finding him slick and open from arousal alone. "You're dripping. This turns you on that much?"
Gen could only nod frantically, words lost in moans. Senku paused the spanking to flip the paddle—ridged side now. The first strike with texture landed and Gen screamed, body convulsing as lines of fire bloomed across his ass. "Too much? Say the word."
"No—don't stop!" Gen begged, voice wrecked. "Need it... need you..."
Finally, Senku dropped the paddle, hands soothing the burning skin before he lined up and thrust in—deep, one stroke. Gen wailed at the fullness, the way the sore flesh pressed against Senku's hips amplifying everything.
Senku fucked him relentlessly, each thrust jolting Gen's reddened ass, reigniting the sting. Gen came first, untouched, ropes of cum spilling as he clenched around Senku, screaming his name. The tightness pulled Senku over— he buried deep, filled Gen, groaning low.
They collapsed, Senku immediately tending: cool cloth, gentle massage, kisses on every mark. "You're incredible," he whispered, holding Gen close as the mentalist floated in subspace, blissed-out and boneless.
Gen smiled weakly.
"Love when you go wild on me."