Sustainable consumption is central to sustainable development goals (SDGs), yet research on consumer behavior (CB) remains scattered. Studies on green consumption, digital retail, fashion, food systems, digital finance, energy, and tourism have developed largely in isolation, and few studies have investigated what these settings share or how sustainability-relevant behavior unfolds after the moment of purchase. This study takes a wider view, applying the SPAR-4-SLR protocol to a decade of CB and sustainability scholarship and combining machine-learning-based BERTopic thematic modeling with SDG mapping, organized through a Theory–Context–Method and Antecedents–Decision–Outcome (TCM–ADO) lens. Seven themes emerged, concentrated on SDGs 8 (decent work), 9 (industry innovation), and 12 (sustainable consumption). Together, they point to a shift away from individual purchase choices toward consumption that is multistage, digitally mediated, and institutionally embedded. Across the seven theme-level summaries, trust, engagement, risk perception, ethics, literacy, and experience appear repeatedly. Because several of these constructs were included in the retrieval query, this pattern is interpreted as cross-theme recurrence within the query-defined corpus rather than as independent evidence of universal prevalence across sustainable consumer-behavior research. Digital and platform mediation appears as one cross-cutting condition, and is most visible where consumption is heavily platform-based. On this basis, the review proposes a process framework that treats antecedents as capability, vulnerability, and layered trust; decisions as multistage and mediated; and outcomes as interdependent SDG bundles. Twelve propositions and a research agenda follow, testable across food, energy, finance, fashion, tourism, and digital retail.