"One dark and eerie night, I stood in front of the bedroom door. As I was about to open it, something unusual happened. Suddenly, someone appeared at the door, slowly as if wanting to speak. Initially, I was startled and thought, 'This might be a thief!' In such a situation, the logical step would be to protect myself. However, as the door opened slowly, what I encountered was not a thief, but an individual dressed in ancient Roman-style royal attire. Their appearance was elegant, with two braided hair strands of dark red color that shone like fire burning in the night, capturing everyone's attention, including my own.

The situation grew more tense as the bedroom door opened. A silent and chilling sound filled the room. Thoughts raced through my mind, 'This thief must be highly skilled. The access required to enter this house is very tight; it seems this thief is very convincing.' I prepared myself to face the threat, even considering the anime figurine I kept as a potential weapon. However, as the door swung open wide, all I found was emptiness in the long and dark corridor. Heavy breaths echoed in the darkness of the night, with slow footsteps that felt like walking on wet ground. Tick-tock, tick-tock, they grew closer...

And from that emptiness, someone mysterious and unexpected emerged, as if coming from an unknown place. They addressed me as 'Sister' while walking like a zombie. Hearing the word 'Sister' made me even more curious about the person who walked like a zombie. Tearfully, they pleaded, 'Sister, can you help me?' Fearful, I thought to myself, 'My heart is almost pounding out of my chest!'

I am a first-year high school student, often considered someone who is used to or familiar with the world. I have a remarkably adorable younger sibling. However, those details about me don't need to be recounted at this moment. The chilling moment of that night came to an end, and it was time to accompany my sibling to the toilet, despite them being in the third year of junior high school.

'Hey, you're already grown up! At least go to the toilet by yourself.'

'Sister, have you ever watched a horror movie at night? Was it scary or just normal?'

'Please listen to this, or I can say it to you, I've warned you not to watch horror movies at night!'

But wait! A horror movie? I began to think about the horror movie I watched with Mari and the fear that might arise if I were to watch it alone. Yes, it's natural to feel scared.

'Phew... It's normal, after all!'

'Sister, what's normal? Stop standing there and quickly accompany me to the toilet!'

'You're really troublesome. Wait a moment, I need to put my figurine back.'

I placed the figurine back on its dedicated shelf and immediately went to the toilet. Once there, I stood next to the toilet, feeling frightened. Initially, I was indeed a scaredy-cat. 'This is not something to be afraid of. Just imagine the anime I watched last night!' I tried to convince myself, even though I still felt scared.

'Mari, how long will you be in the bathroom?'

Ten minutes passed...

There was no sound at all. Only silence filled the air.

'Mari!? Don't scare me!' I grew more scared and anxious. Cold sweat started pouring down, and the hairs on the back of my neck stood up, indicating danger.

'Just to be safe, I'll open the door. Mari, I'm coming in...'

Yet, still no response from Mari

.

With a pounding heart, I slowly opened the bathroom door. The silent creaking of the door intensified my heartbeat due to fear.

'I'm coming in...'

However, what I saw in front of me as I entered the bathroom was truly shocking. My heart raced even faster this time.

'Mari... What are you doing?'

...