This is a study of parasitic intimacy, of unregressable cohabitation – when an animal finds its one true other and survives consuming them. To be the entire world for another, where we are eaten raw by this need, and the constant effort of a companion to keep our harms small, forgivable. This work lays claim to who ‘we’ are, and new ways speak about ‘us’. This is poetry founded in the biological study of parasitic roundworms and the language through which we have come to understand them. There is something here for all of us—a way of knowing that we are not alone—and the lifelong care that we must attempt for each other.