Joo-Young works at a small office and is indifferent to the world. Wanting to separate her personal life from her wor, she buys a used cellphone with the help of which she finds out middle-school student Hee-Joo, the previous owner of the cellphone, is being bullied on social media. Joo-Young, who normally doesn't care about other people, tries to save Hee-Joo.
