Digital video sites currently seek new ways to build a platform to encourage user engagement and enable users to connect with one another through multiple means and channels. The widespread introduction of danmu technology has aroused concerns of academia. However, comparatively little work has been done to explicate the role of danmu function and research progress has been falling behind practical interest. In this study, we seek to investigate user experience and engagement to understand the double-side effect of danmu technology. Using S-O-R framework, we propose that danmu features, namely proximity and coherence, play essential roles in creating augmentation experience of para-social interaction and degradation experience of goal impediment and information overload. Additionally, we investigate user experience to understand user engagement in the danmu-enabled situation. We suggest that para-social interaction will elicit increased user engagement; yet goal impediment and information overload will lead to less user engagement.