Japanese aid has long been criticized for its focus on infrastructural projects, but Japanese aid actors have also valued non-infrastructural soft aid, especially through NGOs. Drawing on twenty months of fieldwork conducted with a Japanese NGO and its training program in sustainable agriculture in Myanmar, this article examines how Japanese and Burmese aid actors engaged in what I call an aid ethic of “muddy labor”—an emphasis on shared physical and relational labor that produced a collective form of intimacy. Scholars have tended to formulate humanitarian moral sentiments as responses to a distant suffering stranger. In contrast, I argue that the ideologies and political effects of a collectivist form of aid emerge in physical, relational, and geographic proximity. I demonstrate how the collective intimacy of physical and relational labor generated a meaningful sense of belonging among aid workers, while Japanese official discourses of soft aid indicated that this ethos of solidarity was also based on hierarchical views of Japanese superiority. The article ultimately asks how this ambiguity of the ethics of muddy labor challenges capacities for critique.