That girl. Black ninja-like costume, black mask, a black beanie.

WHY DIDN'T I CATCH HER IN THE FIRST PLACE!?

"Hey... Whatcha thinkin of?" One of my classmates asked.

I paused and thought for a while.

"Have you seen a girl in ninja-like black costume, a black beanie and black mask?" I asked.

"Not until you mentioned it. Yesterday my sister was wearing the same thing too..." One of my classmates, who's from The U.S named Clarice said.

"Woah, really? What time did she came back home?" I asked.

"You sound like an investigator..." Clarice said.

"One of my close friends almost got killed... My friend described her killer as 'A girl in ninja-like costume, a black beanie and a black mask'..." I said.

"Well, I did overheard her conversation between her friend. I heard her say 'Mission complete'. She sounded like a spy or an agent..." Clarice said.

"Could it be her?" I asked.

"Maybe... Let me go ask her-"

"No thanks... I'll ask. Thanks so much for your help, by the way. Is your sister studying in this school?" I asked.

"She's a grade higher..." Clarice said.

"Okay... I'll try to look for her..." I said.

"Ok," Clarice said.

I've seen Clarice's sister quite a few times, so it's a good thing I can recognize her.

I spot her chatting with one of her friends, I think.

I walked towards her.

"Ummm... I'm Clarice's friend. Can we have a talk?" I asked her.

When she looked at me, she looked shocked. 

"O-Okay..." She said and followed me.

"Ummm... Do you know YoonA?" I asked her.

"Y-Yes... She's my friend's friend..." She said.

"She's almost killed by a girl in black ninja-like costume with a black mask and a black beanie... Have you seen anyone familiar?" I asked, trying to act natural.

"R-Really? YoonA-sshi was almost killed? That's scary..." She said, nervously.

"Do you perhaps think it was Sun Ha?" I asked her.

"I don't think so..." She said.

"Then? Who is it?" I asked.

"I-I don't know..." She said. She was struggling.

"So yesterday, what were you wearing?" I asked.

"My red push-over hoodie with blue jeans... Why?" She asked.

"But your sister, Clarice, told me that you wore a black ninja-like costume with a black mask and a black beanie..." I said, walking step by step to her.

Her eyes widened and she ran all the way to the toilet.

I ran as fast as I could to catch her.

*Damn! She's fast!*

Then, I saw Sehun passing by.

"Sehun-ah! Catch Clarice's sister!" I shouted at him.

He quickly ran to Clarice's direction.

After a few seconds, he finally caught her.

I ran to them.

I heard Clarice's sister shouting "Let me go