What circumstances could have led to this?

Her tits ballooned out for yards on end, straining her green vest to its limits, yet it did not rip or tear, and yet she was growing still. The comparatively tiny body those boobs were attached to hugged them with a mix of awe, fear, and excitement – they weren’t meant to get this big, but it just felt so good, so why should she stop? There wasn’t anything preventing her from stopping, but if anyone could, she could.

The growth started after the Gardevoir came across a black market shop with an odd TM inside, with the proprietor stating she could learn it and it was super powerful. One purchase and move-learning later, she was the proud owner of an illegal move to have on a Gardevoir – Curse. And what effects it had on the first use!

Moaning, the Emotion Pokemon could do naught but hug her tits as they filled up the immediate area, becoming a wall of boob. Her vest continued to stretch and fill out, her mammaries squishing to try and fit into it in a glorious muffintop fit for such a sizable bust. At around fifty feet, they finally stopped, leaving the Gardevoir in a huffing, sweaty mess. Yet she wanted more – she was hooked on that feeling of tightness, of being too large to handle, being the biggest she could be.

Gardevoir used Curse!

The second time around, the effects were much more upscaled; no wonder this move was banned to have for her species, she thought. This was much too good to pass up! Her tits compounded on their growth from before, becoming double what they stopped at within the first minute of growing, and only expanding faster! Trees and buildings couldn’t withstand the growing mass, and admittedly it felt good to feel SOME resistance. Some of the sharp edges began tearing the first of many holes in her vest, her expansive muffintop towering ahead of the green wall barreling forward.

Then there was a glitch. She wasn’t supposed to know this move, and thus her body wasn’t prepared for it. It then learned another move all on its own, adding it as a fifth move on her list – Milk Drink.

Suddenly, as if all at once, her breasts felt fuller than they ever had been. She practically screamed at the feeling, as it was such a sudden rush that she couldn’t even prepare for the levels of pleasure that were filling her. Just knowing the new move was enough to send her boobs into growth overdrive, flattening cities and rolling over hills, edging up on mountains she couldn’t even see if she didn’t have a boobwall in front of her. But she couldn’t use this new move – oh, no, it felt too good to hold in. At her size, though, what could she do to stop it? The thoughts invaded her mind – lactate, milk, lactate, milk – and drove her crazy enough to where she did begin leaking milk and staining her vest.

This would not stand!

Gardevoir used Imprison!

A tight psychic binding wrapped around her nipples, though not on her vest. She gasped and squirmed as their firm holding took effect, though now with those bindings holding her milk back so she can grow further, she wondered just how far she could take it. Even as her tits were still getting up on mountainous sizes, she had enough sense to push her body to use its known moves.

Gardevoir used Curse!

Within ten seconds her boob outgrew the state. Ten times her previous size, and further beyond – yet her milk stayed in, and her body convulsed with primal, pleasure-filled urges. Her legs were soaked with her fluids, her face one of pure ecstasy. But that was just the beginning, she thought – her vest held tight, her boobs still yearning for more despite their protests. Getting ‘too big’ was high on her list of priorities, even as her body was wracked with orgasm after orgasm.

Her tits began to slow down upon reaching the size of the continent, feeling the cold wash of water splash up against them only refueled her energy and cries for more. Her vest was getting thoroughly soaked with it, and all that liquid bouncing her boobs back and forth was just making her think more of the milk currently inside her, building up, wanting oh-so-much to be released onto the world. But she wasn’t going to have it.

Not that she wouldn’t give her breasts a tease of relief, though.

Gardevoir used Milk Drink!

Her growth resumed and only grew from there, expanding into the ocean at record pace. This time, though, it was pure milk filling her – and it was all pushing at her nipples. The bindings held tight, but they pulsed and inflated with the milk as her need increased, the move wanting to fully execute but being prevented from doing so by her own Imprison. Feeling on top of the world – literally and figuratively, considering her tits were entering orbit at this point – the Gardevoir could do nothing but scream in pleasure, her moveset aimed totally at expanding her bust beyond reasonable doubt.

Yet, she still had enough energy to use those moves. And with each climax, she could feel it flow into her, experience and levels beyond what’s normally possible. Good for her, because she wasn’t about to stop anytime soon.

Gardevoir used Curse!

Gardevoir used Milk Drink!

There wasn’t a single Pokemon that could stop her from growing her tits into the atmosphere, becoming planets in their own right. Her vest was finally showing signs of ripping, her bulging muffintop pushing it to its absolute limits while the rest of her tits still contained within pushing those holes larger and larger, wanting to be free, wanting to fill out more space.

The only thoughts within the Gardevoir’s mind now were simple thoughts. “Milk”, “boobs”, “bigger”, “Curse”, “Milk Drink”…she cycled through these each millisecond, desiring nothing more than to make her boobs as big as possible.

She kept using those moves. Over, and over, and over…and over…an infinite amount of uses. She didn’t feel there was any reason to hold back.

With each use, she felt her vest rip more and more until it was finally burst open, and feel her exponential growth compare to the other obstacles in the galaxy. Planets bounced against her bust, and stars made for a warm massage. She outgrew any black holes that tried to suck her in, and her nipples were all too happy to poke through her ripping vest and really show off how full they were as they too began pushing planets and stars themselves as the rest of her bust felt millions of planetary bodies push into her skin like a massive, growing, yet tiny and pinpointed massage.

In her lust, however, she forgot about her Imprison bindings. As her boobs grew even more full and her nipples even more denied of their milking, the sheer power of the googolplexian gallons of milk surging about within her began taking force with all those move uses. The need eventually began to be so much that her nubs began sinking into her puffy nipples as it prepared itself for a milky explosion, and when she used one too many Milk Drinks, both of her nipples were ready to blow.

Gardevoir used Milk Drink!

And blow they did. The bindings broke and her nubs resurged outwards, spraying an impossibly thick geyser of milk out of each. Her boobs were sent flying backwards from the force, all the way to the edge of the universe where they grew and bounced against the universal barrier keeping her intact. That was next on her list, she thought, but at the forefront of her barely-operating mind was her milk. Oh Arceus, her milk. It felt immeasurably pleasureful to finally release all that pent-up milk, but she was still growing. But what was growing faster was her output, enough to where once she had reached the barrier, she had already filled a quarter of the universe with her milk.

Her tits, barely edging on thousands of galaxies large, was not even a speck in comparison to how much milk she had let out so far. Feeling her nipples flex and pulse as they continued to let out ever more milk, she was now split – did she want to get bigger? Did she want to lactate more?

It’s not like it mattered anymore. She was going to get bigger either way. With her two glitched moves, she could gain however much size or milk she wanted, and she wanted it all.

Might as well see how far she can take it on one end until she passes out.

Gardevoir used Milk Drink!

Gardevoir used Milk Drink!

Gardevoir used Milk Drink!

Gardevoir used Milk Drink!