When they entered the school gate, they saw an unusual scene. Dahyun wasn't sitting in one of the benches.

The truth is that Dahyun was actually waiting for the gang to arrived since last week even though she acts cold towards them. But, today seems different. Dahyun wasn't there.

"Where is that tofu?" Nayeon asked

They decided to shrug it off and went to their class. Recess time came and there's still no sign of Dahyun.

Chaeyoung had an idea why but she isn't sure. She needed proof. So while the others are eating in the cafeteria, Chaeyoung stood up.

"I got to go to the library."

"Okay."

Chaeyoung went out of the cafeteria and headed to their clubroom, hoping Dahyun was there. But she wasn't. Chaeyoung sighed and headed to the second floor. She went to Dahyun's class and looked at the door. Dahyun chair is vacant.

"Hey."

Chaeyoung turned around and saw the girl Dahyun talks to, last time.

"Uhh...hello, sunbae."

"Looking for Dahyun?"

"Uhh. Yeah. How did you know?"

"You're Son Chaeyoung, right? I'm SinB."

"Annyeong, SinB sunbae."

"If you're looking for Dahyun, she's absent today. I don't know why."

"Oh."

'I was right. That idiot unnie.'

"Well then, I got to go. See you, sunbae."

"Yeah."

"Thank you."

"You're welcome."

Chaeyoung heard the bell rang so she went back to class. She saw that Tzuyu is already in her seat.

"Where have you been?"

"Second floor."

"Did you see Dahyun unnie?"

"No. She's absent."

"Oh."

"I think I'm going to skip class later in the afternoon."

"WHAT?" Tzuyu exclaimed "Why?"

"I think I know why she's absent and I'm going to their mansion."

"Alright."

"Don't tell the unnies where I am, okay?"

"Yeah, sure."

"Promise?"

"Yes, I promise."

"Good. Better keep your words, Chou Tzuyu."

"What are you going to do there, anyway?"

"I'm going to murder someone."

"You're scaring me, Chae. Stop that. But, eat your lunch first, kay?"

Chaeyoung didn't answered Tzuyu and focused on her lesson. She really want to fast forward things so that she can leave, now.

Finally, lunch time came. She packed her things before heading to the cafeteria. The others didn't know why Chaeyoung was bringing her bag in the cafeteria but Tzuyu lied that they'll be changing classrooms later.

Chaeyoung hurriedly finished her food and was about to leave when Mina grab her hand.

"What?"

"Uhh...I have something to tell you."

"What is it? Please hurry up."

"Okay. Are you free tomorrow?" 

Tomorrow is Saturday so Chaeyoung nodded. She really wants to leave now.

"Great. Meet me up in the mall, tomorrow at 5PM. Is that okay?"

"Yeah, yeah. Look, I got to go. See you."

Chaeyoung left the cafeteria and rode the bus. Meanwhile in the cafeteria...Momo suddenly stood up and left, too.

Everyone looked at Mina.

"What?"

"Bad move, Myoui." Jeongyeon said

"Huh?"

"Better run after her." Nayeon suggested

Mina mentally facepalmed when she realized that she did something again in front of Momo. She stood up and left the others.

"Poor Momoring." Jeongyeon said and she received a slap from Nayeon "Ouch! Why did you do that?"

"Will you please shut up?"

"I'm just saying."

Mina went to the third floor and went to Momo's class. Mina and Sana are classmate but Momo is in the advanced class. She may be slow or being called idiot but she's definitely not dumb. She's unexpectedly a genius. Mina saw Momo sitting in her chair while wearing headphones and playing in her phone.

"Hey." Mina called one of Momo's classmate.

"Yes? What can I do for the Black Swan?" t