Chapter 1

"Sometimes, we build up an invisible wall in our heart. Maybe we were hurt or maybe not. But I believe you and I all have a beautiful heart behind it"

Yeji and Lia lived in a city. Decades ago, the city had been split into two parts for some reasons. A long wall was set up overnight.

Yeji found that Lia was a lonely girl, while Lia found that Yeji was always avoiding things in her words. They met other girls too and each girl brought their stories with them.

They were drawn into memories again and again. An explosion, a secret group, their lives were closely intertwined with the crisis of the city.