The book is designed for foreign learners who want to learn Korean through actual Korean Wave content, away from formalized school textbooks. In most cases, a book is made to incorporate Korean Wave into Korean language education, but this book was made while thinking about how to effectively utilize BTS' various contents in Korean language education. So it's not boring but fun. In addition, the sound pen translates eye-viewing into ear-listening so that Korean comes to live sound. Besides, isn't the character BTS that we really want to meet? Yes, Let's learn Korean with BTS!!!