Redondoviruses are almost exclusively found in the oro-respiratory tract of humans. They are highly prevalent in healthy individuals, and their abundance is increased in individuals with different conditions like periodontitis, critical and inflammatory diseases and COVID-19. These viruses are circular Rep-encoding single-stranded DNA viruses, and their cell host is currently unknown. In this new study, Keeler et al. explore which type of human cell supports redondovirus replication, and they surprisingly discover that the eukaryotic commensal amoeba Entamoeba gingivalis is their main host. The authors investigated redondovirus phylogeny and guanine-cytosine content, and found that it was consistent with E. gingivalis being the host. Analysis of metagenomics datasets from individuals with oral disease and healthy individuals revealed co-occurrence of E. gingivalis and redondoviruses in both groups. In vitro, E. gingivalis grown in xenic culture in the absence of human cells was able to produce redondoviruses, and viral and protozoan DNA were co-localized. Altogether, these findings point at E. gingivalis as the host for redondovirus replication and highlight the potential contributions of eukaryotic commensal viruses to the human virome.