We settled for a little one-story house not far from where we started. The fridge had food in it, and no one was at home, so that was a success. The door was locked, but the window was already busted. It looked like they were already victims of whatever this mess was. Not wanting to be a repeat, we got to work fortifying, and soon had the windows boarded up with anything we could find. We left the door unbarred, just deadbolted. We might have to get out eventually. Our food supply was good, but far from infinite. Maybe a week, if we ate light.
That evening, enjoying a can of beans that made me feel like we were truly living the apocalyptic life, I felt bad. Maybe it was all the running around and excitement, but I was tired and I had a headache. Sandra seemed to notice and pat my arm. "You look awful. Want to go lay down?" I did, so I did. I fell onto the bed and tried to go to sleep, but it refused to come. The headache was growing worse by the moment, robbing me of any chance of a nap. The bed shuffled as Sandra settled on it beside me and rolled me onto my back. She put a wet cloth on my head. "You're an idiot, you know that? You didn't have to go with me. You probably pricked your finger on a nail or something and you'll die of dysentery."
I laughed a little. "You don't get dysentery from nails, that's, uh, bad water. Rusty nails is... Fuck, what was that, uh, tetanus. I've had my shots for that anyway. It's not that."
Sandra frowned. "Speaking of that, who's to say the water's safe anymore? What if those horse things get into the supply? I doubt many people will be manning the water pumps while all this goes on."
I had no particular good answers. "We'll have to make do with bottled water for now." Sudden lethargy washed over me, and sleep came like a wave, and I was out.
I was back in that garden. The dark-furred horse was there. Luna, I think her name was? She looked at me sadly. She had surprisingly human expressions. She took a half-step towards me, "Do you understand me?" I nodded. "Ah, I thought you would already be gone. Creature, I know not much of your species, but I am aware your world is in great peril. I have not reached anypony else, so I will tell you, even if you are doomed. An experiment has gone afoul. Instead of reaching a new world, we sent our essence through, and it became contaminated in the space between worlds. You are experiencing our very soul, warped and perverted by the void. I can only shudder to think of what form it may take."
I woke up to being shaken by Sandra. She looked scared. "What? What is it?" She pointed up above my eyes, at my forehead. I reached up and found the nub of something protruding. Was it a horn? I slipped out of bed and rushed to the bathroom to look at myself. Yep, a horn, a very light pink horn. Crap. "Shit."
Sandra came up beside me and wrapped an arm around, squeezing lightly. "We've got each other, right?"
We were never 'an item', just friends, but we did have each other, and I was very glad to not be alone. I held her close. "I don't feel different, I mean, besides having a horn. I'm not crazy."
She nodded. "I... It's hard to explain, but I feel like there's something I should be looking for. I'm afraid, William. What if I got crazy like the rest of them?"
I put my hands on her shoulders, squeezing gently. "I'll keep you safe. I'll tie you down until you get over it, if I have to."
She snorted. "What if I never 'get over it'? I don't want to be some brainless horse... thing."
I thought back to my dream, but there was nothing there that'd calm Sandra down. "Look, we'll do what we can. We'll survive, day by day."
So that's what we did. The next day had Sandra with a big red tail, and she grew fuzzy ears in the afternoon of the same brilliant color. She kept looking towards the door like she wanted to go, but she didn't go. My horn grew in stupidly long, but nothing else happened. I tried to use the magic I saw the unicorn doing and after a few hours of work, I could summon the remote from across the room. Score! The feat seemed to amuse Sandra. "At least you got something useful out of it."
The day after that. Sandra had abandoned her pants entirely. Her big tail and reshaped legs just didn't fit them anymore, so she was naked from the hips down. She looked to the door constantly. "I want to go, William... I want to find others. I have to. Please, let me go." She scratched at her increasingly furry hips. "I'm going crazy being stuck in here. I won't find anyone in here. I have to go look for them. I have to."
I shook her a little. "Sandy, hold it together. If you go out there, you'll be a brainless horse and you'll hunt people, innocent people. Is this really what you want to give?"
She shook her head, tears squeezing from her shut eyes. "No, but I have to. William, help me. I have to..." She made a sudden lunge for the door and I jumped after her, tackling her to the ground. Her tail twitched between us like an angry snake as she tried to escape, but I held firmly to her and slowly managed to drag her away. She broke down into fresh tears. "I can't stop thinking about finding them! It won't leave me alone!"
With her depressed instead of trying to escape, I quickly grabbed some cords and got to tying her up, which she allowed me to do in a moment of clarity. I soon had her sitting in a chair, tied as securely as I could manage it. I looked her over. She was like a satyr now, all pony from the hips down to her new hooves, with that bright red tail twitching angrily. She had big horse ears instead of her human ones. There was still intelligence in her eyes, but it seemed to come and go as she was gripped by the urge to spread her 'gift' to everyone else. She didn't have a horn or wings or that split-jaw thing, so she was pretty normal as colorful horses went.
She dozed off, and I sat across from her on the couch, watching her. The change kept spreading, awake or not, fur going up under her shirt and her hair turning the same bright red before it lightened to an off-orange shade. I leaned around and saw her tail had lightened as well, matching her... mane? Her torso made unsettling noises as she started to adopt the shape of a horse, and I carefully extracted her from her shirt and let her grow into her new self.
I awoke the next day to find her looking at me with a new long face. The only human parts she had left were her arms and hands. She looked away when she noticed I was examining her. "I'm hideous."
I slid to my unchanged feet and looked myself over. I was the same horned human that fell asleep, if a bit stinky for not changing clothes. "You feel better today?"
"Sort of..." She wriggled in her restraints. "I still want to go, but it's not... quite as bad. Thank you, Will. Don't you feel it at all?"
I shook my head. "I don't feel anything but hungry right now. Speaking of which, we've only got enough bottled water for today at best."
Her ears fell as she shrank, which was kind of cute in a horrific way. "If I go outside, I might never come back."
I nodded slowly. "Yeah... so I'll leave you here, and go myself. What's the worst they could do? I'm already infected, right?"
She smiled. "Oh, now you're looking forward to sloppy kisses from horse people?"
"If it's you, I'd get over it quick."
She blushed, which should have been impossible. Not only did she have fur, but the fur was already red. Somehow she showed even more red through it.
"I'll try the Safeway. It's only a few blocks away."
She sighed. "Everyone will try there, be careful. People are just as dangerous. Do you have something to cover that horn with?"
"Good call." I reached up for the horn. Why did it have to be so damned long? I searched the house and eventually settled for a towel wrapped around like one of those middle-eastern looks done completely wrong. "Ta da!"
She snorted, a noise she was better able to make with that snout. "You look awful, but less like a unicorn. Get back as soon as you can, and safely."
I nodded and grabbed the backpack. It was do or die time, and I wasn't much a fan of death.