In order to explain the Urge to Impulse Buy (UIB) in Pakistan's high-risk social-commerce environment, this study creates and empirically investigates a novel mediation framework. Brand Intimacy Motive (BIM), Shopping Planning Motive (SPM), and Entertainment Motive (ETM) are their three main digital consumption motives. The research suggests that these motivations do not always result in impulsive behavior, which goes against conventional wisdom. Instead, the relationship is mediated by Trust in Online Sellers (TOS), which is crucial due to widespread concerns over fraud, counterfeit products, and inconsistent seller credibility in the Pakistani market. The framework hypothesizes that high TOS acts as a critical psychological filter, reducing perceived risk and enabling the energy from BIM, SPM, and ETM to convert into UIB (H4, H5, H6). Furthermore, it is anticipated that TOS will directly improve UIB (H7). Utilizing a quantitative, cross-sectional design and data from active Pakistani social-commerce users, this study employs the PROCESS macro in SPSS for mediation analysis. The results will give digital marketers, platforms, and legislators practical insights on how to strike a balance between compelling digital triggers and crucial trust-building mechanisms in developing, risk-sensitive markets. They will also offer a modern, trust-centered understanding of digital impulse buying.