Your sister, Bonnie.

“What do you need sis?” You asked turning around. “I’m kind of b-”

Bonnie sauntered over and despite your best efforts you couldn’t conceal the awe on your face as you drank in her appearance. Her enlarged breasts strained against a small, slightly torn shirt that you vaguely recognised as one of Tori’s, while the only thing she wore below the waist was a blue thong that just barely covered her shaved womanhood and hiked up into the tight cheeks of her delicious ass. With every step she took she vibrated sex appeal and confidence.

There was a small grin of triumph on her face as she closed the distance between you, delighting in the way you gawked at her so openly. She threw her arms around your neck and looked up at you affectionately, her very presence causing your groin to stir to life.

“How are you doing?” She asked, noting the small bruise on your jaw, “still feel like you went five rounds with Mike Tyson?”

“Well, I can just about talk in complete sentences again without having to swallow a quart of my own blood, so that’s something.”

Bonnie nodded, began to rub the back of your neck affectionately. It was strange being so close to her in this situation, even though every inch of her being, from the way she smiled to the press of her firm, supple body against you oozed raw sexuality, there was still a degree of big sisterly instinct about her. It was confusing, but also comforting in its way.

“So, some of the guys mentioned you might be going out again today,” she tilted her head, “is that right?”

“Well, I don’t like it,” you sighed, very aware of every ache and twinge of pain that still remained across your body, “but...I kind of feel like I probably should. It’ll save us a lot of time and effort if I chaperone the guys while we do the supply run .”

“Do you think you could possibly make a detour,” she asked, “to the observatory? ”

You winced a little at the thought. “Sorry sis, that sounds like it would be a massive trip on its own, and I’ve already got a busy enough day as is. We need to prioritise getting supplies for everyone first. Maybe we can go tomorrow instead.”

She chewed on her bottom lip, considering for a moment. “Ok...then, is there any chance I can come with you on the supply run?”

That caught you off guard. “Is there something you need? Because you know I can get it for you while I’m out, you don’t need to put yourself in danger...”

“It’s better if I come with you,” she insisted. “There are a few bits and pieces that I’ll need to help set up shop here. Tools, batteries, spare parts, wiring...”

Another thing that comforted you. When you were kids Bonnie would be all over anything mechanical, anything she could take apart and put back together. You grandfather even used to joke around and call her “Q” after the James Bond character, which was cute then and comforting now. This was still Bonnie, your nerdy, amazing big sister.

“Ok you can come,” you replied after mulling over the idea, “but you’ve got to stick close to me the entire time, Ok? You never know what’s out there.”

A smile broke across her face and she reached up and pulled you into a sudden and forceful kiss, her tongue massaging your own as she moaned into your mouth. Very quickly you found yourself melting into the kiss, your hands beginning to lower and grab a handful of her toned ass.

Sanity returned and you broke away, but you were both flushed with arousal as you stood in the hallway, caressing each other’s bodies. You stared into her adoring eyes, “Isn’t it weird for you?”

“What, fucking my brother?”

“Well, that too,” you laughed, “but...I mean...you were purely a lesbian before this happened. And now...

“And now I find your cock to be one of the most delightful things in the world,” she finished, nodding to herself. “Yeah, it’s strange. I mean, I still prefer women, I still love Gabby. That hasn’t changed, but it’s like,” her eyes scanned the distance, searching for an answer, “it’s like...when it comes to you, preference doesn’t matter. I know deep inside of me that if I fuck you it’ll be the greatest feeling ever.” She shrugged. “I don’t really know, Mr Robbins thinks my brain chemistry is changing.”

You grew still at that. If the old biologist was really making some kind of a breakthrough with all of this then visiting him would have to be another thing to mark off on your to-do list for the day.

The two of you parted and went about getting ready. Three groups were assembled taking three different trucks, including Alan’s, though your friend had elected to stay behind today. Mr Spellman waved you over to his vehicle, pausing only momentarily to frown at your sister’s state of dress. She thrown on a pair of sneakers, but otherwise remained scantly clad.

“It’s gonna be a while before I get used to that,” he muttered, ushering you both into the truck. Bonnie got into the back with another of your friends, Adam, while you were in front with Spellman. “Everyone good?” The old man asked, “Then let’s get this show on the road.”

The convoy of vehicles rolled out through the battered neighbourhood and out into the apocalyptic streets of the city. You could still see a lot of smoke coming from one of the doused house fires, and wondered how many people got hurt before the militia got to the scene. It was crazy to think that your family friends and neighbours were essentially the closest thing to law and order right now.

The drive was quiet and uneventful. Nobody spoke, but Bonnie gasped a little as she took in each new sight of devastation. You felt an instinctive pang of worry, though realistically you knew you couldn’t shield your loved ones from the horrors of the new world.

Spellman pulled into the parking lot of the local S-Mart, squinting at every thing and anything. There were a few abandoned cars, and some overturned shopping karts, but for the most part the place was pretty desolate and from the outside there was no sign of life within the store.

The other vehicles quickly emptied of men, six in total, including Blaine, who had brought batons with him that he was handing out. You also noted that everyone was armed and instinctively touched your shoulder, feeling the phantom pain of the tranq round.

“Look alive,” Spellman grunted, “I’m sure you’ve all seen Dawn of the Dead...”

Bonnie instinctively drew close to you, and your fingers intwined with her own as your group began to approach the store. You gave her a reassuring squeeze before venturing inside...