You need more.

You take both vials and dump them down your throat greedily. The oily taste you once hated has become your new perverse favorite flavor. You let out a raucous belch and moan as you feel your body shudder again with that familiar heat and feel your eternally hard cock throb as it grows a couple extra inches and your balls swell another size up. After a month of endless conditioning at the hands of Prince Brynn you've grown to adore your place as his pet. Perhaps all the stuffing and your constant 'milking' sessions were warping your mind, but the more you grow the more brutish and lustful you become to get bigger. Bigger. Bigger to serve your prince more. You pant lustfully. Even though Brynn had just milked you dry just a few minutes ago your cock is already so hard it hurts. Pushing up against your supple underbelly like a metal rod to where you can just see your brawny head peeking out past the horizon of your fat tits and burgeoning belly thanks to its new length. It's the first time you've been able to see any part of your cock in a month. Before now it's been constantly obscured beneath your expanding blubber. The only sign of its presence being when you felt Prince Brynn's mouth wrapped around it or when a fellow pet came around to milk a load into a golden dish when Brynn was not available to do so himself. Seeing it now and how much bigger it's grown creates a feedback loop of arousal that floods your mind of all rational thought except for one.

Bigger.

You want to get bigger. No -- you need to get bigger. A need so intense and carnal you can't even control yourself. You pant hard as you reach over to the box of yellow potion and pull it over to you in bed. The servant who's guarding you looks alarmed and starts to move to stop you but is interrupted by the booming voice of the Prince coming from outside the chamber.

"CAN NONE OF YOU DO ANYTHING *BWUOOARRPP* RIGHT, YOU WORTHLESS SODS!? I ASKED FOR SABELEN CHAMPAGNE NOT FJORDIAN!!"

The guard took a few confused takes, torn between his obligations, before rushing out to try and quell the Prince's fifth temper tantrum today. With no one to stop you, you turn back to the crate of potion. Since the new month had rolled around, the crate was almost completely full of the beautiful vials of yellow liquid you so desperately craved. Without any hesitation you began tearing corks out of them left and right before pouring each and every vial's contents down your greedy maw. Before you even know it, you've consumed a whole month's worth of growth potion in the blink of an eye. You lay there for a moment trying to process what's happened when suddenly your body goes hot. As hot as a blacksmith's forge. You writhe as your whole body is wracked by an intense invisible ****. Your cock throbs harder and harder as you see it rapidly grow before your eyes, getting thicker as it extends ever higher, and you feel your balls pushing your flabby legs apart as they swell out of control as well. The feeling is absolutely euphoric as you watch yourself growing bigger, and bigger, and bigger. However, that's not the only change you notice happening. Soon you feel your smooth skin growing thick and leathery, brown patches of velvety hide with spots of white cropping up and growing until they overtake all of your skin. Your hand and feet tingle as they morph and contort into strange hoof-like versions of themselves. You watch in perverse horror as you see your face starting to elongate into a more animal-like form as horns start to sprout from your temples. Somewhere beneath your bed-ridden lard you can feel a tail sprout between your ample ass cheeks. You have no clue what's happening, but for some reason it feels absolutely ecstatic. You feel so good, you can't control yourself as your towering cock shudders before erupting with the first of several massive loads and you let out a long droning moan that sounds more like a moo as you continue to fire off gallon after gallon of cum which sprays all over your belly.

When the transformation finally subsides you're left a literal cow with a monstrous cock that's longer than your torso and thicker than the average Grasian peasant, with balls so large and swollen with cum each one would need a wheelbarrow of its own to move, chocolate brown hide with splotches of cream, a pair of powerful curved horns flanking your head, and coated in a sticky mess of your own seed.