It takes the last of your strength to pry open the seal on one of the milk cartons. It's not the neatest job you've ever done on a carton, but at least it's open. You tip the heavy vessel into the air and let the cool refreshing milk flood your dry mouth. It washes gently down your throat and into your stomach, bringing with it a relief even greater than you expected. It feels like rain in the desert.
Before you realize it, you've gulped down the entire carton. Your strength already seems to be returning. You grab another one from the still-open fridge and practically rip the entire top off as you open it. This one tastes even better than the first, and it's gone just as quickly.
Having downed an entire gallon of milk, you sit down on the floor and let your stomach digest for a moment. You breathe a sigh of relief and gently nudge the fridge door closed. You scoot over a bit so you can lean your back against a cupboard. It feels so much better to have a full stomach. It's so full it's actually pulling the otherwise loose overalls tight across your belly. You rub it gently and wait to regain more strength.
You come to the strange realization that your overalls are tightening in other areas, too. It's starting to feel tight around your hips, and the straps are pulling harder on your shoulders. You slowly get to your feet, feeling the milk slosh around in your stomach. The overalls are definitely fitting better now. Instead of feeling a couple sizes too big, they feel just right.
"What's happening," you think to yourself. Surely a gallon of milk couldn't cause you to gain weight like this...especially not so fast. You see some kind of discoloration on your arms. They're getting darker even as you watch them.
"Oh no," you groan. Apparently nothing was without consequence in this house. You spend the night, you get younger. You drink milk...
The thought disgusts you, yet there is a small part of you that finds this entire ordeal fascinating. You try to push that thought aside, however, as you wonder what you were going to do to reverse what was happening. You briefly consider going to the bathroom and sticking your finger down your throat when a pain shoots up your spine. It intensifies to the point where you almost lose all sensation, and then you hear a rip.
The pain fades, and now you feel an odd tugging in your tailbone area. You don't want to admit to yourself what has just happened, but when you feel something scrape the outside of the overalls' legs, you force yourself to look behind you.
Sure enough, a long fleshy tail is dangling from a hole torn in the seat of the overalls. It's thin, skin-colored with small black spots, and ends in a fluffy tuft of brown hair. You look at the rest of your body and see that the discolored areas of your skin have completely darkened into the black spots of a cow. The rest remains the same color as before.
You're mad at yourself for drinking the milk. You wish you had left the house and found something to eat in the forest. You know how futile it would have been, realizing you were so weak you probably wouldn't have made it far away from the house before collapsing. You try to reason with yourself, trying to feel glad you didn't eat the carrots or the cheese. But is being a cow better than a rabbit or a mouse? Better than starving to death? You aren't sure.
Meanwhile, your changes continue. You brace yourself against the kitchen counter as your feet reshape themselves. They grow longer, heels rising off the floor as your toes blacken and harden into large hooves. Your fingers crush themselves together until you're left with only two thick fingers and a thumb on each hand, all with wide, black fingernails.
Now the overalls are starting to feel constricting, especially around your waist. As your body continues to gain muscle and fat, the overalls that felt two sizes too large when you were in the throes of hunger have now become two sizes too small. Your hips strain the thick denim, and your nether regions scrape the tightening fabric, sending your brain sensations you'd rather not dwell on right now.
You try to think which is better; tight-fitting overalls or walking around naked in your half-cow form. Your body doesn't seem to be growing anymore, except for your breasts. They've been slowly swelling, unnoticed along with the other changes, but now they're the only things to attract your attention. They've passes a few cup sizes already, and now they're looking a little disproportionate, even on your slightly bulkier frame. Your nipples are pressed uncomfortably against the denim, reminding you of your tight crotch. The growth of your breasts strains the thick straps around your shoulders. They no longer sag against your chest, instead pulled completely taut in the air between your shoulders and the tops of your breasts. The front of the overalls strains to support the bulbous mammaries as they swell full of the milk you just drank. It's feeling very sensitive now, and you find yourself groping your large nipples through the denim. Another hand slowly finds its way to your crotch as the changes finish.
You pull yourself out of your daze. Your breasts have stopped growing, and just in time. Any larger and it seemed you'd be bursting out of the only clothes you had. The overalls are uncomfortably tight. You even wonder if you can get yourself out of them. You grope the strap's buttons. The steel feels cold against your large breasts, only making the sensations you're trying to ignore worse. The metal buttons aren't the snap kind, but the actual button kind, and at the moment it's impossible to get your thick fingers underneath them. The fabric is just stretched too tight. You push it into your breasts to try and loosen it, but that does nothing besides send more shivers down your spine.
You resolve not to try that again, and look about for a mirror. Your heels clack on the tile floor as you approach the windows. You can faintly see your reflection in the glass. Your face doesn't look any different, except for the spots. A large black one circles your left eye, another one dots your right cheek, and other small spots are splashed around your face. You can clearly see four pointy things sticking out of your head. Two of them are your cow horns, curving out from the top of your hair. The other two are large, long ears that you realize can move in any direction. Finally, your long brown hair has gained several black streaks.
Your body is a little bulkier, obviously, but you don't look fatter. You've probably gained a few inches in height, and dozens of pounds, but it feels to be mostly muscle. You flex your right arm, feeling a newfound strength. The transformation could have been a lot worse, you suppose, but right now you'd rather be a plain human being and far away from this strange house.