Chapter 1

Mark often brought packages home from work—research equipment, spare components, the occasional experimental gadget. But today, something far more intriguing sat in his hands—a sleek black case, about the size of a shoebox, its metallic sheen catching the dim kitchen light.He set his keys down and placed the case on the counter, fingers running along its smooth, unmarked surface. No logos, no labels—just a small touch screen on the side.

“This is it?” Sarah asked, peeking over from her workspace in the living room, a stylus twirling idly between her fingers.

Mark nodded, pressing his thumb against the touchscreen. A soft beep, then a mechanical click. The case split open with a hiss of depressurized air, revealing the device inside—a futuristic-looking gun, sleek and ergonomic, its illuminated display casting a faint glow.

Sarah raised an eyebrow. “That’s the portal thing?”

Mark chuckled. “Portal gun sounds too sci-fi, but yeah. This is the prototype I was telling you about. My colleagues were kind enough to let me test it before official trials.”

He lifted it carefully, feeling the weight. It was heavier than it looked, likely from the dense wiring and quantum circuitry packed inside. The research team at the scientific center had spent years developing it, and now, it was finally ready for real-world testing. The premise was simple: Create two linking portals and reduce travel time between distant places to mere seconds. The applications were limitless—instant commutes, effortless international travel.

Sarah leaned in, intrigued. “So… you just shoot at two surfaces, and boom—instant doorway?”

“Pretty much.” Mark grinned, giving the gun a small spin in his hand, his confidence betrayed by his clumsy grip. The device slipped from his fingers, clattering onto the counter. A faint spark could be heard from it.

Sarah sighed, crossing her arms. “Mark.”

“I know, I know.” He scooped it up quickly, sheepish. “I’ll be careful.”

She wasn’t exaggerating. Mark had a special talent for mishaps. Whether it was tripping over his own feet, catching a cold from the slightest breeze, once even managing to sprain his wrist by opening a jar too aggressively., he always needed looking after. Sarah didn’t mind—he was endearing in his own way—but that didn’t make it easy.

Especially considering their height difference. At 165 cm (5’5), she wasn’t short, in fact she was average, but Mark’s 188 cm (6’2) frame meant that whenever he sprawled sick on the couch, moving him was impossible. Carrying him to bed? Out of the question. Reaching for things he absentmindedly placed on the highest shelves? A daily frustration. Heavy chores around the apartment? He took care of them—because she physically couldn’t.

She had started exercising recently, hoping to get stronger, to be more independent, but it wasn’t easy. She hated the idea of going to the gym, surrounded by strangers. The stares, the noise, the social anxiety—it was all too much. So far, jogging was her best option, but even that meant navigating crowded sidewalks, traffic lights, and the occasional odd glance.

Mark set the gun back in its case. “Let’s leave it for now. We can test it properly in the coming weeks. I’ll show you how it works tomorrow if you—”

But Sarah wasn’t listening anymore. Her mind was racing.

Sarah rarely left the apartment. As a freelance artist, she had no reason to—not when everything she needed was within arm’s reach. Outside trips were strictly for groceries or the occasional visit to her mother’s place in the countryside, both of which felt more like obligations than outings. But now, as she turned the sleek device over in her hands, she could already see how much easier it could make her life. No more long drives, no more gas station stops. The thought alone had her mentally tallying up the savings.

“Sarah, I know you are already daydreaming about the possibilities, but at least read the instructions before using it”, Mark said.

Mark always joked about her uncanny ability to predict their grocery bill down to the cent before they even reached checkout, but it wasn’t just some quirk—it was a skill. She had a way of breaking things down, spotting patterns, finding the most efficient path forward. And right now, her brain was working overtime, mapping out all the ways this little piece of tech could cut costs and save time.

But even more than that, there was something else. A realization forming in the back of her mind, small but insistent.

She had always hated jogging outside—too many people, too many distractions, too many eyes. But if she could create two portals, perfectly aligned…

She could do her run inside. No obstacles. No interruptions. Just pure, uninterrupted movement.

A plan formed in her mind.

__________

The next morning, with Mark out of the apartment to go to the office, Sarah stood alone in the middle of their apartment, portal gun in hand.

“Alright, let’s see if this works.”

She aimed at the far wall, pressing the trigger. A bright flash, followed by a swirling blue ellipse forming on the surface. Turning, she fired again at the opposite wall, exactly several meters away. A second portal appeared, shimmering slightly before stabilizing.

Sarah took a deep breath and stepped forward. The moment she passed through, she emerged seamlessly from the other side, back at her starting point. She spun around, looking at the portals with wide eyes.

“It works.”

A grin spread across her face. If these were stable, she could jog infinitely without ever leaving the apartment. Sarah changed into her exercising clothes, stretched, set a timer, and started jogging. The exhilaration of moving, of exercising without anyone watching, sent a thrill through her.

She fell into a rhythm quickly, the portals making it feel almost hypnotic. Six meters forward, Whoomp—another six meters. The smooth transition was seamless, like stepping through a mirror. She barely even noticed the passage of time, lost in the motion.

But there was something she didn’t notice.

A flaw.

The portals weren’t identical.

One was ever so slightly larger than the other—an imperceptible discrepancy, but a discrepancy nonetheless. With every pass, every step through the shimmering gates, her body subtly adjusted. Minutely expanded. A fraction of a fraction.

But over time, fractions add up.

After around a thousand cycles—Sarah finally stopped, wiping sweat from her brow. She took a deep breath, her heart pounding from the exertion. She sipped from her water bottle to quench the thirst.

Then, she noticed something strange.

The bottle felt… smaller.

Her fingers curled around it, feeling how different it sat in her grasp. She frowned, rolling it between her palms.

Her stomach twisted. That couldn’t be right.

Sarah glanced around the apartment. The furniture, the walls—it was all the same, wasn’t it? But something felt wrong, like a subtle shift in perspective she couldn’t quite place. Her pulse quickened. Maybe it was just the exhaustion? A trick of the light?

She then tried to grab the door handle to the bathroom slightly missing her initial attempt to grasp it.

Her breath hitched.

“No. That was impossible. What’s happening”

She hurried to the mirror, almost afraid of what she’d see..Her reflection met her at a slightly higher angle. Not by much—just a little taller—but enough to be noticeable. Heart pounding, she grabbed a measuring tape, pressing it to the wall where she had marked her height months ago.

174 cm (5’8).

Her breath came in shallow gasps. That couldn’t be right.

She was supposed to be 165 cm (5’5) tall.

Sarah stared at the number, her mind racing. That was impossible. Absolutely impossible. She backed up, looking at the still-active portals with a dawning realization.

“Oh, shit.”