I'm infamous for being the stupidest student in the entire school. Even though I've been doing additional revisions till late night every day, I keep getting the lowest rank consistently in exams.

On the other hand, my younger sister, Mia Lawson, doesn't study at all. Yet, she always comes up as the top of her grade every time. Our parents soon call her as the Math Prodigy.

Because of that, I'm forced to live in the attic, which leaks all the time during rainy days. My table lamp gets smashed into pieces as well since I shouldn't be wasting power if I can't cram any knowledge into my brain.

My parents also force me to drop out of school and start working at a young age. They claim that losers should stick to their paths and do what they do best. But at the same time, they don't hesitate to drop a grand sum of money just to enroll Mia into a class based on the Arithmetiad.

There's a time when I contract a high fever that makes me all woozy and my consciousness all blurry. Because of my illness, I randomly draw an incorrect construction line on a draft paper.

The next day, the line actually appears on Mia's exam paper, pixel by pixel.

That's when realization dawns on me immediately.

Before the day the National Arithmetiad is set to be streamed live in front of the entire nation, I opt to not solve any difficult questions.

Instead, I lock my room door and keep telling myself in front of the mirror that the greatest mathematical equation in this world is 1+1=3.

"Solana, where's your pay for this month? And where the hell have you been?"

Mom's shrill voice pierced through the thin wooden boards of the attic, buzzing in my ears like a drill.

I dragged my exhausted body down the stairs and handed over the 4,000 dollars I had just been paid.

She snatched it from me, pulled out the bills, and, right in front of me, flicked through them with saliva-wet fingers, counting at speed. Then, her brows twisted into a tight knot.

"That's it? 4,000 dollars is barely enough to buy Mia's supplements! I bet you've just been slacking off at the factory!"

My younger sister, Mia Lawson, stepped out wearing a brand-new white flowy dress, emerging from my room—no, her room now.

She carried a plate of apple slices cut into little bunny shapes. Without sparing me a glance, she went straight to Mom and Dad, her voice soft and spoiled.

"Mom, Dad, the finals will be held in Washburn. Flights and hotels aren't cheap."

Dad picked it up immediately. "My good girl, don't you worry about money. You've got your sister for that."

He turned to me, eyes cold, as if he were looking at a faulty tool. "You hear that? Talk to your factory boss and get next month's pay in advance. And quit walking around like a corpse all day!

"The only value you have is being a stepping stone for your sister. Worked to death? That's your blessing. Don't act like you don't know what's good for you!"

The house was spotless, bright from end to end. Only I stood there, stained and out of place, like I never belonged there.

Mia picked up a slice of apple and chewed it slowly, her eyes sliding toward me, amused, like a cat toying with a mouse. "Solana, you'd better work hard."

She lifted her wrist and showed off her brand-new smartwatch. I had seen it online. The price was exactly 4,000 dollars.

"After all," she continued, "this family is counting on that tiny bit you bring to the table."

Mom chimed in right away. "Your sister's right. That's your only value. We had you just to pave the way for Mia!"

I looked at the three of them, warm and happy together, while the smell of machine oil clung to me no matter how hard I scrubbed. My stomach churned. I lowered my eyes and tucked every emotion away.

"I understand."

Seeing how docile I was, Dad relaxed a little. Mia, on the other hand, wasn't satisfied.

She padded over in her fluffy slippers, stopped in front of me, and lowered her voice to a whisper only I could hear. "You've changed, Solana. You would've run off and cried in secret had this happened in the past. You're killing the fun."

I raised my head and looked at her quietly. The face that shared 70% of my features carried nothing but the smug glow of a victor.

Back then, I could never make sense of it.

I studied like my life depended on it, pushed myself to the brink, and nearly burned myself out, only to get beatings and scoldings from my parents, as well as mockery from Mia.

She, on the other hand, had a desk full of comics and novels, yet she could take first place in every competition without breaking a sweat.

Teachers praised her. The media put her on a pedestal and called her a once-in-a-century genius.

It never added up… until a week ago.

I had a fever that climbed to 104 degrees Fahrenheit. My head was spinning, my thoughts slipping out of focus. A kind woman at the factory brought me home, but my parents said I was bad luck and dumped me in the attic to fend for myself.

Half-conscious, burning up, I grabbed a scrap sheet and started sketching out a geometry problem. I drew an auxiliary line, got it wrong, and without thinking, scribbled a crooked little turtle beside it.

The next day, the fever broke. I went downstairs for water and saw Mia's weekly math test lying on the table. The last question on the paper was the same geometry problem I had worked on the night before.

In her solution, there was that same incorrect auxiliary line. Right next to it, a crooked little turtle, identical to mine, sat quietly on the page.

The teacher must have taken it for some kind of special notation. There was even a red circle beside it, with a comment that read, "Unusual, but interesting approach."

At that moment, the blood in my body ran cold.

Mia wasn't a genius. She was just a shameless thief.

A memory suddenly surfaced.

When I was little, I once had a high fever that wouldn't break. In my delirium, I felt like another "me" was fighting for something inside my mind.

When I finally woke up, Mia was suddenly able to recite a classical poem I had only just learned. Meanwhile, I couldn't remember a single word of it.

From that day on, it felt like there was a hole in my head. At critical moments, I would be hit by a strange emptiness, as if something had been siphoned away from me.

Mia had been stealing from me—my thoughts, my knowledge, every problem I solved late into the night, and even the absent doodles I didn't think twice about.

Faced with my silence, Mia lost interest and pouted. "Mom, Dad, I'm heading to my Arithmetiad class. Do Solana's earnings even cover my intensive training fees? I heard it's ten thousand a month."

Mom immediately put on a fawning smile. "Of course, they do. I'll borrow more if I have to. Mia, just focus on your studies and don't get distracted!"

I watched Mia's proud back as she walked away.

My hand slid into my pocket and tightened around a wrinkled scrap of paper I had hidden. On it, written in thick red ink, was "1+1=3".

The next day, I didn't go to the factory. Instead, I went back to school.

When my homeroom teacher, Mr. Boyle, saw me, his eyes were full of pity and confusion. "Solana, what are you doing here? Did something… happen? Are you in trouble?"

It was the final stretch of senior year, the most critical period, and I had chosen to drop out right at its edge. All the teachers thought I had given up on myself, but they didn't know the truth.

Mom and Dad had personally come to school with my withdrawal form. In front of all the teachers, they said I wasn't cut out for studying and would be better off if I worked and supported my genius sister, Mia.

I shook my head and took out a stack of money from my pocket. It was slightly damp with sweat. I placed it on his desk. This was everything I had secretly saved. Even the registration fee had been borrowed after I begged a woman at the factory.

"Mr. Boyle, I'd like to participate in the National Arithmetiad this year."

Mr. Boyle froze. He adjusted his glasses, his expression conflicted. "Solana, this isn't something to joke about. You haven't been attending classes for a long time. And besides, your grades…"

He didn't finish, but I understood what he meant. In this school, I was the epitome of dumb.

Every day, I was the first one to arrive in the classroom and the last one to leave. My scratch paper piled up like a small mountain, yet my scores always hovered at the very bottom, either last or second-last place.

Everyone said the same thing—Solana Lawson simply wasn't made for studying.

I looked at Mr. Boyle and spoke clearly, word by word. "Mr. Boyle, please give me a chance."

There was no pleading in my eyes, only a cold, unyielding resolve.

In the end, he let out a long sigh and took the money. "Fine. I'll register you as an independent candidate. But Solana, don't set your hopes too high. Just think of it as going for the experience."

"Thanks, Mr. Boyle."

I thanked him and turned to leave.

When I returned to my so-called home, Mia was sitting on the couch with her legs crossed, ordering Mom around as she peeled an apple for her. The peel couldn't even break once.

When she saw me, she frowned. "Why are you back so early today? Did the factory finally fire your useless ass?"

I ignored her and walked straight toward the stairs leading up to the attic.

"Stand right there!" Mia suddenly screamed. "I'm talking to you! Are you deaf or what?"

I paused and turned back to look at her, my expression flat. "I quit my job."

"What?"

Not only Mia, but even Mom and Dad, who had been busy in the kitchen, rushed out like startled cats whose tails had been stepped on.

Mom charged at me, hand raised to slap me across the face. "Have you gone crazy, you brat? How can you just quit a stable job like that? What about Mia's tutoring fees next month? Are we supposed to starve because of you?"

I tilted my body and dodged. Her nails scraped across my cheek, leaving a burning sting behind. Coldly, I looked at Mom. "I registered for the National Arithmetiad."

The living room went dead silent for three seconds before it erupted into loud, apologetic laughter.

Mia bent over, laughing so hard tears formed in her eyes. "Solana, did your fever fry your brain? With that dim wit of yours, you're taking part in a math competition?

"What, are you going there just to fill a seat and show everyone how to score zero?"

Dad pointed at my face, his voice booming with anger. "You don't know your place, do you? Who do you think you are? You think you're Mia? Not everyone can dream of being a genius like her!

"I'm telling you, Solana, if you dare embarrass our family name, I'll break your leg!"

I looked at their twisted faces, feeling nothing but a cold emptiness. "And if I win the championship, then what?"

Mia's laughter stopped abruptly. She looked me up and down, contempt practically spilling from her eyes. "Championship? Solana, if you can win first place, I'll admit defeat in front of the whole country and eat this damn book!"

She kicked at the Arithmetiad book sticking out of her bag.

I met her eyes and said confidently, "Fine. We have a deal."

With that, I ignored my family's lashings and curses from behind and returned to the attic.

I knew the moment I said I was going to enter the National Arithmetiad, Mia had already started "stealing". Like a greedy thief, she would siphon off everything from my head.

Every concept I had built up, every problem type I had drilled, every formula I had distilled and memorized, she would copy them all. Then, in the exam hall, she would turn them all into her own glory.

Unfortunately for her, I had prepared a special gift for her with my mind, one big enough to ruin everything she had.

For the next two weeks, I shut myself up in the attic and cut off the world.

I didn't grind through problem assets like before. Instead, I found a cracked mirror I had picked up from the trash. Every day, I stood in front of it and stared at the gaunt version of myself, repeating the same line over and over like self-hypnosis.

"One plus one equals three."

Every time I said it, it felt like two steel needles were drilling into my temples. Nausea rose in my throat. My brain, the entire framework of logic and proofs I had spent years constructing, was violently rejecting that absurd conclusion.

But I couldn't stop. I dug my nails into my arm, hard enough to bite into the flesh, using the pain to fight off the dizziness.

"One plus one equals three! It equals three!" I snarled at my reflection.

The version of me in the mirror looked skeletal, eyes sunken deep, staring back with a mocking curl at the corner of her mouth. My mind was screaming. Every neuron was pushing back against the absurdity.

The mold creeping across the walls seemed to come alive, twisting into crooked little "2"s that laughed at me.

I slammed my fist into the wall, letting the sharp burst of pain crush the dizziness. "No, it's three!"

I dragged myself back in front of the mirror, nails digging into my palm until I could taste blood in the air, just so I could keep myself anchored.

"I'll say it again. One plus one equals three. Pi is an integer. It's four! You hear me? It's four! Between two points, the curve is the shortest path. Yeah, the curve is the shortest!"

I laughed in between my words. "The sum of the interior angles of a triangle… is 360 degrees. Yeah, 360!"

I started hallucinating. Wrong formulas crawled out of my books like black insects, swarming across the pages before burrowing into my ears and nose.

Night after night, I couldn't sleep. The moment I closed my eyes, I saw Mia's smug face, along with Mom and Dad's curses ringing in my head.

So, I stayed awake, pacing the attic over and over, muttering those twisted truths under my breath.

I knew how Mia's strange ability worked. She didn't steal surface thoughts. She stole what I believed at my core, the axioms etched into my subconscious.

Only when I truly believed, down to the marrow, that one plus one equaled three, would she copy it without hesitation and write it out in the nationally televised examination hall, sealing her own downfall with her own hand.

When Mom and Dad saw me holed up in the attic all day, acting like I had lost my mind, it only made them angrier. In return, they cut off my food entirely.

Every time it was meal time, Mom would shout at the top of her lungs downstairs, "Solana, you useless brat! Get a job and stop leeching off us! You must be in over your head!

"Once Mia wins the championship, you'll have no reason to stay in this house anymore! By then, I'll kick you out without a second thought!"

The attic was stifling, thick with heat and stale air. Hunger left me dizzy, my vision swimming, my lips cracked. I ended up going to the bathroom just to drink tap water and keep myself going.

Still, the pain in my body was nothing compared to what was happening in my mind.

Downstairs, Mia lived like a princess.

I had no idea where Mom and Dad got the money—probably high-interest loans—but they hired her the most expensive private tutors for a final push.

They bought her the latest phone so she could relax. Every day, they provided her with the most advanced nutritional products, served like she was made of glass, as if even losing a strand of hair would ruin everything.

Sometimes, when she was in a particularly good mood, she would come up to the attic door. I always kept it locked from the inside.

She would knock, then speak in that lofty, pitying tone. "Solana, I really feel sorry for you. We're both Mom and Dad's children, so how did you end up this stupid? Stay in that moldy attic and keep dreaming about your championship.

"Oh, right. My tutor praised me again today, said I'm definitely taking first place in the finals."

I never answered her. Every bit of strength I had was spent fighting my own mind, forcing it to accept that warped system of truths, a ridiculous mathematical world that belonged to only both of us.

At last, the day of the competition arrived.

Mia and I walked into the examination hall together. She was the prodigy everyone had their eyes on. Dressed in a designer dress, she was surrounded by reporters and team coaches, camera flashes popping nonstop.

Meanwhile, I was in a faded old T-shirt, just an unnoticed independent candidate who had signed up on my own.

Before we went in, Mia made a point of walking over to me. The perfume on her was so strong it stung.

She chuckled contemptuously. It wasn't loud, but it carried just enough for the nearby reporters to hear. "Good luck, Solana. Don't score a zero and embarrass Mom and Dad."

I looked at her confident face and smiled from the bottom of my heart. "Good luck to you, too."