Video Sharing Platforms (VSPs) are increasingly incorporating a novel feature that enables users to embed comments directly into the video timeline while viewing the video. Known as ‘danmaku’, this feature allows users to watch a video alongside danmaku comments and embed their spontaneous reactions directly into the video timeline. Drawing on the needs-affordance-feature perspective and social information processing theory, we explain why users use the danmaku feature and how that shapes their social experience through two novel affordances, which we conceptualize as pseudo-synchronous viewing affordance (PSVA) and pseudo-synchronous responding affordance (PSRA). The study contributes to the literature by conceptualizing and validating the novel affordances of PSVA and PSRA and examining how they shape users’ social experiences. It also has practical implications for VSP companies and VSP users.