Separated by a glass wall, the only connection they have is each other, they must learn to love, and learn to escape.

Park Sojin is eighteen years old and lives in the psychiatric hospital. She is kept in a blank room with barely anything in. Nobody knows what's wrong with her, apart from she has a big issue in controlling her anger, setting her free would be a huge mistake.

Lee Hyeri is sixteen years old and also lives in the psychiatric hospital. She stays in her very colourful room with all her books and likes to draw. Her parents abandoned her at the hospital, and nobody knows why she was abandoned, or what lead to the deterioration of her mental state.

There is a glass wall separating the two girls. They become best friends, but can never leave their rooms together. The only way they communicate is the gap at the bottom of the glass. Hyeri gives Sojin her pictures, and Sojin keeps all the pictures and puts them on the walls of her room to make it look nicer. They only have each other, and that's what keeps them happy.