>Bottomheavy futa, with a huge ass, extra-wide hips, and thick thighs which frame her massive, heavy, productive grapefruit-sized balls and meaty, thick slab of girthy cock perfectly
>Everyone jokes about how she's hung like a horse, a few actively tease her in public, most people have seen the resulting absurd bulge
>She's got a super passive temperment, trying to endure even when she's about to flood an entire room in thick spunk
>Eventually, her many fans and bullies grow bold enough to enact an incredibly lewd plan

>She's tied down and edged mercilessly for hours
>Drug-laced lube which increases sensitivity slathered all over her shaft and balls as countless hands worship her, always stopping just before she can cum
>It doesn't take long for her balls to start working triple-time producing the thickest, gooiest cum possible, but they don't stop there

>Bring out a strange device and bucket after bucket clearly overflowing with thick, steaming-hot, pure white sperm as gooey as tar
>They work one end of the device down into her urethra slowly, the sensation of being invaded keeping her on a constant hair-trigger, painfully close to climax
>Once in place, they reveal what it does- there's a large container at the top, and anything put into it will drain down... directly into her balls
>The buckets are overflowing with freshly donated loads from purebred stallions, a particularly proud lineage of breeders with record-breakingly large and heavy balls and unfathomably virile loads

>Bucket after bucket is dumped in as it slowly flows down, she thrashes and wails as she can feel it oozing down into her fat ballsack and begin mingling with her own sperm, making her balls grow warmer and even more active as she fills
>Her balls grow larger, hotter, and heavier with every passing moment, the container never getting any closer to empty thanks to the sperm buckets and fresh donations from excited fans
>It feels worryingly good
>Even when her balls are unbearably laden with unfathomably dense, heavy horse-gunk, darkening in color and aching from the sheer overload, even as more forces its way down, she stays steel-hard, hints of pleasured moans slipping into her pleas for mercy and wailing

>Eventually she's so full that no more can flow in on its own, her balls filled to the very brim with mixed ball-sludge begging to escape, writhing in the sweet agony of needing to cum in the worst possible way but being unable to release
>They don't stop there- they start forcing it down the tube, adding pressure to make it flow again, adding further to the immense backlog of steaming-hot, hyperactive white sludge packing in tighter and tighter
>Only when she has the most severe case of blueballs possible do they stop, leaving her balls packed to the absolute limit with three parts fresh purebred horse seed and one part her own vigorous swimmers

>More edging, although they can't do very much without nearly losing all control, even a single feather being nearly too much after only a few minutes
>Her wild pleas to cum are ignored as a special, tight, golden cock-ring is placed around the base of her painfully engorged, throbbing, absurdly-thick shaft
>Her bursting blue balls ache so hellishly, full past the brim and still generating more baby-batter, screaming for immediate release- ignoring the tight ring ensuring that she cannot possibly express even a single drop of her rapidly aging, thickening, fermenting load of sperm
>The ring isn't coming off for an entire month at the absolute least, by which time her own natural production rate and the pressure of her densely-packed balls will make it more a 1:1 mix of stallion seed to her own, and the two will be totally indistinguishable from each other at that point; let alone how it will thicken to the point of near-solid sludge and grow so angrily pungent and potent that her balls will radiate intense heat and pheromone-laden musk, ache agonizingly at all hours of the day, and slowly become nastier and off-color the longer she's forced to contain it

>There's no guarantee they'll relent after just one month, especially if she won't meet certain demands, such as drinking every drop of her then intolerably pungent loads or reaching climax exclusively through urethral insertion

>The entire time, feeling her impossibly full balls pushing past their limits at an agonizingly slow pace keeps her on the edge of orgasm, she's never not rock-hard even without teasing. Knowing what she'll have to do to earn release, knowing that she'll willingly let it happen again, makes her cock twitch and throb with shameless desire...