Deleuze and Guattari’s conception of a minor literature—linguistically deterritorialised, thoroughly political, and collectively charged—can allow us to draw parallels between distant, diverse literatures; demographic and historical similarities, such as numerical ultra-smallness, do so as well. This essay compares literatures which are both minor and ultrasmall: ultraminor, as Bergur Moberg has recently coined. It looks at the ways in which attitudes towards diversity have shaped the representation of foreigners and “the foreign” in genre fiction. It argues that the emergence and popularity of the respective genres—romance in Mauritius and thriller in Norway—is tied to societal responses to demographic concerns. Focusing on two representative novels, Natacha Appanah’s Blue Bay Palace and Gunnar Staalesen’s We Shall Inherit the Wind, it further argues that Mauritians view the instability of diversity as an inescapable starting point, while Bergenseres view this instability as a frightening, however welcomed, resolution.