This research attends to how urban tenants bring matong (toilets in the form of urine buckets)—which are a material, semiotic, and marketable piece of infrastructure—into the debates over the remaking of a heritage district in Hongkou, Shanghai. Challenges abound for the site, which is occupied by prewar buildings where Jewish refugees found shelter during the war and more than 10 thousand Chinese tenants moved in after the Jews left. Until 2020, the dilapidated buildings accommodated an aging population of tenants who wish to stay relevant to the redevelopment vision of Shanghai and a variety of community business, including urban waste recycling. To find a crack in the state-led, neoliberal system, the tenants managed to exercise infrapolitics —an everyday form of resistance—over an urban infrastructure that is of particular significance to their bio-well-being and beyond. We analyze a set of spatial politics on sanatory infrastructure in Hongkou to understand how the tenants are desperately capitalizing on their disadvantages and reassembling memories, waste, and housing inequality into something more promising from below. The theorization of infra-bio-urbanism upon toilets sheds light on the accumulating anxiety upon housing inequality and infrastructural mobility in globalizing cities in China and beyond.