With the international rise of K-pop culture, this analysis of BTS and the languages surrounding and related to their music, fans, and media content provides a unique look into how languages are localized, hybridized, and utilized beyond popular entertainment. Drawing on a wide range of data, the book examines various BTS-related content, from their music to the content generated by both BTS themselves and their fans. Chapters explore key sociolinguistic issues using BTS's language as data, including their songs, lyrics, tweets, and interviews, and languages of BTS consumers, including fan interactions, reaction videos, commercials, as well as BTS-inspired signs and sounds in public places. With their phenomenal success in the global music market and ever-dominant presence on social media, BTS has inspired scholarly interest in academic fields such as culture and media studies, musicology, sociology, and business marketing, shedding light on effective communication and innovative language use. As the very first scholarly collection on BTS-related language, this book will be of interest to students and scholars studying language use and communication, including linguistic hybridity, multimodality, translanguaging practices, and multilingual communication.