After borrowing it from her roommate Karina and reading it, aespa’s Ningning recommended Lee Gi-ju’s book The Temperature of Language on Bubble. Published in 2016, the book has continued to appear on bestseller lists, and many people still quote it. It draws attention to things we have overlooked and offers comfort about things we take for granted. Ningning’s roommate Karina is said to have introduced her to the book when Ningning said she wanted to learn Korean.