This chapter aims to clarify the types of relationships that could serve as the elementary units of a relational ontology by exploring two key concepts of internal relationships exemplified by Robinson Crusoe’s journey: one structural and impersonal, the other intersubjective and personal. By examining these contrasting, ideal-typical relational modes, the chapter proposes an intermediate model of relationality – what M. Mauss and G. Simmel describe as the “relational in-between.” This mode, distinct from structural and intersubjective relations, concerns social forms of exchange and “the strength of the bond” they can create. After outlining these generic social forms, the chapter argues for a grammatical approach to social relations, conceptualizing them as a system of places governed by constitutive rules and practically implemented as normative affordances. This framework allows for articulating a grammar and a phenomenology of the social bond, which is tested through Favret-Saada’s ethnography of witchcraft. Finally, the chapter moves from a descriptive to a normative perspective, examining the kind of relationship that should ideally serve as the foundation of the social world.