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The pipes groaned like old bones that night, rattling through the walls of their suburban home. Mark sighed, rubbing his tired eyes. At thirty-four, office work drained him, but plumbing disasters? Those were a special kind of hell. "Looks like only the master bath tub works, Ben," he called out to his nine-year-old son. "Hot water heater's acting up too. Might be best if we share tonight. Conserve what we've got."
Ben's face lit up, pure excitement chasing away any hint of bedtime reluctance. "Really? Like an adventure!" He bounced on his feet, already tugging off his Spider-Man pajama top. Mark watched him, a familiar warmth spreading in his chest – paternal pride, he told himself firmly. Just pride.
The bathroom quickly filled with steam. Mark sank into the deep tub first; the warm water soothed his aching muscles. Ben hurried in after him, small and thin, splashing water everywhere as he settled between Mark's legs, his back against the opposite side of the tub from his father. The contrast was stark: Mark's broad, hairy figure on one side and Ben's smooth, youthful figure on the other. Innocence contrasted with the firmness and muscularity of adulthood.
"That's so hot," Ben murmured, wiggling his toes. He tilted his head back to look at his father. "Why is your dicky bigger than mine, Daddy?" His finger pointed vaguely beneath the water, toward Mark's lap. The question was casual, curious, lacking any understanding beyond the simple physical difference. Like asking why the sky was blue.
Mark froze; the heat suddenly felt oppressive. "Just... grown-up stuff, mate," he managed in a strained voice. He focused on the tile pattern above the faucet, counting the blue squares. "Don't react. It's nothing. He doesn't know," he thought.
Ben laughed, accepting the answer easily. He scooped up a handful of water and playfully splashed it toward his father's stomach; the drops falling onto his father's chest created a new sensation for him. Mark shuddered, a pang of unwanted self-consciousness passing through him.
"Wash my back?" Ben asked, turning around in the tub and presenting his smooth shoulders to his father. Mark swallowed and reached for the soap. His hands trembled slightly as he lathered the boy's skin, running over the delicate bumps of his spine. He concentrated on the task, the scent of a clean, soapy boy filling his nose. "I'm just washing my son. Normal. Fatherly," he insisted in his head as if trying to convince himself, knowing in advance that he was losing the battle, since his penis between his legs was gradually getting bigger and bigger...
Then Ben moved again, stretching his legs, and stood up when he felt his father's hands reach the edge of the water.
"Go on, Daddy! Wash me all over!" the boy said, excited and confused by this new feeling of well-being that was overwhelming him, although he didn't quite understand it.
Mark gasped, taking a deep breath that he couldn't hold back when Ben's soft, round bottom was right in front of his face. His whole body went paralyzed.
Ben froze too. The water lapped gently against his thighs. He felt his father's trembling fingers slide down his lower back, past the curve of his spine, and settle on the swell of his buttocks. It wasn't soapy anymore. It was slow, deliberate pressure. A thumb traced the cleft between his cheeks, exploring with a tenderness that made Ben shiver. A strange warmth pooled low in his belly, unfamiliar and thrilling. His own little cock twitched against his thigh, stiffening in a way he'd never felt before.
Mark's control shattered. He leaned forward, his broad shoulders blocking the light. His soap-free hand gently parted Ben's cheeks. The boy gasped softly as warm, wet pressure bloomed against his most private place. His father's tongue pressed firmly against his tight, hairless opening, probing, tasting. It wasn't rough, but insistent. Ben's eyes flew wide. Confusion warred with a sudden, overwhelming wave of pleasure. Without thought, he pushed back against the pressure, arching his spine. A tiny, breathless moan escaped him. The water rippled around his hardening erection.
The sensation was electric. Ben's small body trembled violently. His hands gripped the cool porcelain edge of the tub. His hips jerked forward once, twice – sharp, involuntary thrusts into the warm water. Then his whole frame locked. His mouth opened in a silent cry as pure, white-hot ecstasy ripped through him. It wasn't wet. It was a dry, pulsing explosion deep inside his core, leaving him dizzy and panting. At the exact moment Ben convulsed, Mark groaned, a deep, guttural sound muffled against his son's skin. His hips bucked violently. Thick ropes of semen pulsed from his straining cock, swirling milky-white into the bathwater between Ben's trembling legs. The tub filled with the sharp, musky scent of release. Mark slumped forward, his forehead resting against the small of Ben's back, breathing raggedly. Silence descended, thick and heavy, broken only by the frantic beating of two hearts and the drip of the faulty faucet. Mark knew. He knew exactly what he'd done. The line wasn't just crossed; it was obliterated. Slowly, dreading what he might see, he lifted his head. Ben turned. His cheeks were flushed pink, his lips parted. But his eyes... they weren't scared. They were wide, dark pools reflecting the bathroom light, shimmering with something raw, hungry, and utterly new. Desire. Pure, uncomplicated desire, fixed solely on his father. Mark's eyes light up with lust: their relationship have changed forever. And he couldn't be happier.