This study examines interactions in an extensive reading (ER) book club intended to provide opportunities for students to practice English as their second language (L2). Utilizing multimodal conversation analysis, the study shows how students display willingness to participate (WTP) when they are free to initiate or avoid communication. The analysis of seven and a half hours of videorecordings of meetings held over six weeks at a Korean university demonstrates that several practices, particularly responding to questions and expanding on storytelling, reflect WTP. The study particularly highlights the importance of non-verbal cues in signaling and managing the WTP. The study suggests that student initiative can lead to more interactive and engaging learning environments, which may be especially significant in L2 settings where promoting student talk is a primary objective. The findings have implications for educators regarding the dynamics of student participation and agency, and contribute to our understanding of the nuanced relationships between learner initiative and WTP in fluency-oriented language learning contexts.