While research on peer feedback in the L2 writing classroom has proliferated over the past three decades, only limited attention has been paid to how students respond to their peers' writing in specific contexts and why they respond in the ways they do. As a result, much remains to be known about how individual differences and contextual influences shape L2 students' peer feedback practices. To bridge the research gap, this case study examines two Chinese EFL university students' peer feedback practices and the factors influencing their feedback practices. Analyses of multiple sources of data including interviews, video recordings of peer feedback sessions, stimulated recalls, and texts reveal that the students took markedly different approaches when responding to their peers' writing. The findings also indicate that their peer feedback practices were situated in their own distinct sociocultural context and mediated by a myriad of factors including beliefs and values, motives and goals, secondary school learning and feedback experience, teacher feedback practices, feedback training, feedback group dynamics, as well as learning and assessment culture.