Emma and Sophia, two fiercely competitive sisters, collapsed onto the mats of their home gym after an intense session, their bodies glistening from the effort. Both had been pushing their limits with heavy lifts, and lately their midsections were transforming into thick, rippling muscleguts while their breasts swelled larger and heavier with each gain. "Look at that abs on you, sis," Emma teased, poking Sophia's hardening core. "You're turning into a damn tank. Bet you think that makes you the alpha now?"
Sophia flexed back, her large breasts straining against her sports bra as she smirked. "Alpha? Please, Emma. Your gut's catching up fast, and those tits are practically begging for attention. But if we're being honest, this muscle is making me horny as hell. You feeling it too?"
The air thickened with tension as they locked eyes, witty barbs flying like foreplay. "Horny? I'm dripping just watching you pump iron," Emma shot back, her voice sharp. "Think you can handle what I've got growing?" Sophia leaned in, assertive and unyielding. "Handle it? I'll ride it till you beg. But first, show me that ass you've been sculpting."
Clothes hit the floor in a rush of sweating skin and panting breaths. Sophia grabbed a strap-on from their gear bag, strapping the hard cock into place with a wicked grin. "On your knees for a blowjob, sis? Or are you too strong to submit?" Emma laughed, pushing her onto her back instead. "You wish. I'll take that cock first—watch how wet my pussy gets for it."
Emma mounted her sister, guiding the thick cock into her dripping pussy with a groan, her musclegut flexing as she rode hard. Sophia thrust up, gripping Emma's swelling ass while their large breasts bounced together. "Fuck, you're tight and horny," Sophia panted, "but I'm not cumming until you do." They switched, Emma on all fours as Sophia pounded from behind, the room echoing with moans and the slap of muscle on muscle.
Both sisters came hard, cum dripping down thighs as they collapsed in a sweaty heap, bodies still twitching from the release. "That was just the warm-up," Emma whispered, tracing Sophia's pumped gut. "Our gains are only getting bigger—and so is this taboo thrill."
The sisters exchanged a knowing glance, already plotting their next intense session together.
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