Mobile short-form video entertainment enables mainstream public sites to expedite the dissemination of essential information, increase transparency, and maintain trust among decision-making bodies. In view of these benefits, it is necessary to understand the mechanism of citizen engagement with short-form videos using social media almetrics. The purpose of this study is to delineate the driving factors and moderating effects of large-scale interactive participation in TikTok's public accounts committed to sustainable poverty alleviation, a grand challenge that spreads quickly on the official agenda. Specifically, this study estimates negative binomial models based on the complete set of videos, released between 2018 August (the earliest date available) and September 2021, in poverty-striken provinces. The results show that appropriate combinations of common themes, music genres, and sentiment values can strengthen the involvement and awareness of short-form video entertainment. It serves as convincing proof that 1) content related to human resource development and public policies stimulated the highest level of citizen engagement, and it exceeded all other categories by a large margin; 2) the moderating roles of sentiment values could be partially confirmed across the common themes and music genres; and 3) while being moderated, popular and epic music could either arise or weaken citizen engagement under the topical series, but the benefits of containing these genres were not limited to performance.