When the Serial Killer Next Door Gained Harem System

We had an exam on January fifteenth. English. I was only seven, and honestly, my exams had been terrible up until that point. I could barely focus in class because of all the pills my mother had been giving me. Most days I felt either sick or completely numb, like my body did not belong to me. I had no energy to do anything, and even when I tried, it felt like I was moving through mud.

But in her own way, she believed she was helping me. She thought she was protecting me from ending up like my sister.

Then things changed.

The exam date was moved forward to January fourteenth. I took it without much confidence and walked out thinking I had failed badly.

But when the results came back, I had gotten a B+.

Even I was surprised.

I felt... happy. Really happy.

After school ended, I rushed home as fast as I could, holding the paper tightly in my hand. When my mother opened the door, I held it up with a smile I could not contain.

"Mom!" I said. "I got a B+!"

"B+?" she repeated slowly. "But the exam is tomorrow."

She stood in the doorway, pale as always, her skin almost colorless under the dim hallway light. Her long black hair hung loosely around her shoulders, slightly unkempt, and her eyes carried that same distant, uneasy look they always had, like she was never fully present in the moment.

"We took the exam early, Mom," I said, still smiling. "I got a B+."

"No... no, no..." Her voice shifted, tightening with something sharper. "The exam is tomorrow."

My smile faded.

"No, Mom... they—"

"Doppelgänger!" she suddenly screamed.

I flinched.

"One of those doppelgängers the government sent!"

"Mom!"

"Don’t ’Mom’ me!" she snapped, leaning forward and snatching the paper from my hands. She tore it apart in front of me, the pieces falling to the floor. "Get out of here!"

"Mom... it’s me!"

"Doppelgänger!"

I did not even know what that word meant at the time. I just stood there, confused and scared, trying to understand what was happening.

"I’m not him, Mother!" I shouted. "I’m Ace. Your son!"

"STOP IT!"

She slammed the door in my face.

I stepped forward immediately and started banging on it. The cold hit me almost at once. Snow was falling outside, and even the apartment corridor felt freezing.

"Mom! Let me in!"

There was no answer.

"Mom, please!"

The door suddenly opened. For a moment, I felt relief. Then I saw what she was holding... a teapot. Before I could react, she threw it. Boiling water crashed against me.

I screamed as the heat tore across my skin, the pain immediate and overwhelming. My body jerked back instinctively, and I lost my footing, tumbling down the stairs behind me. Everything blurred.

I fell down the stairs, hitting the steps hard, one after another, until I finally stopped at the bottom. My head spun, and something warm ran into my eyes, mixing with the cold.

Through the haze, I looked up. She was already closing the door. There was no hesitation. No regret.

Just the sound of it shutting.

"Mother..." I whispered, my voice breaking. "Please..."

"Get up, Ace."

I opened my eyes and saw Mio standing in front of me, already dressed in her school uniform. It took me a second to process where I was. I had fallen asleep sitting on the couch, with my own uniform still resting on my lap. Yesterday had been exhausting, and I vaguely remembered closing my eyes for just a moment before planning to check the system. I must have passed out immediately.

"Oh... shit," I muttered as I pushed myself up. "Ugh..."

"Uncomfortable?" she asked. "It has to be."

"Yeah," I said, getting to my feet and rubbing my face. "What time is it?"

"Eight thirty," she replied. "Come on. Get up."

I rolled my shoulder, testing it. It still hurt, but not as bad as before. "Right... okay."

"You can wash your face outside."

"Alright... let me wear this first."

"Okay. I’ll wait for you outside." 𝒻𝓇𝑒𝘦𝘸𝑒𝒷𝓃ℴ𝑣𝘦𝑙.𝒸ℴ𝘮

Mio stepped out of the house and closed the door behind her, leaving me alone inside.

I picked up the uniform from my lap and quickly changed, pulling the tunic over my head and adjusting it until it sat properly on my shoulders. The fabric felt lighter than what I had been wearing before, cleaner too. Once I finished, I rolled my shoulder again, testing the movement. There was still a dull ache, but it was manageable.

I glanced toward the small mirror on the wall and took a step closer, giving myself a quick look. The uniform fit well enough, and for once, I did not look like I had just crawled out of a ditch.

"Not bad," I muttered.

I then looked down at my old clothes, now in my hands. Carrying them around would be awkward, especially like this.

As I stared at them, something appeared in front of me. A faint, translucent circle formed in the air.

I frowned slightly and focused on it. The moment I did, the circle began to fill, like it was responding to my attention. Symbols and faint lines formed within it, shaping into something more structured.

A prompt appeared. It was asking if I wanted to store the clothes in my inventory.

I hesitated for a second, then shifted my gaze toward the option marked "Yes."

The moment I focused on it, the system responded. The selection triggered on its own.

A soft golden light spread over the clothes in my hands, and before I could even react, they dissolved into that light and vanished completely. The entire process took less than a second, leaving my hands empty.

The interface updated immediately.

╔═════════════════╗

> INVENTORY

╠═════════════════╣

>Basic Tunic

>Plain Trousers

>Worn Shoes

> (EMPTY)

> (EMPTY)

───────────────────

> Coin: 0

╚═════════════════╝

I stared at it for a moment, then let out a quiet breath.

"Damn... useful..."

I went out, closing the door. Mio was across the street, yawning. .Just a few steps away from the entrance, there was a large wooden water trough, filled nearly to the brim.

I leaned over it, scooped up some water, and splashed it onto my face. The cold hit instantly, waking me up more effectively than anything else could have. I exhaled and ran my wet hands over my face again before straightening up.

We started walking.