We study the free PROP on a single binary generator . The ancestry functor , defined by connected components of the underlying undirected string diagram, has image the sub-PROP of finite corelations whose equivalence classes contain exactly one input and at least one output. The induced quotient [ :=(δ)/\ker(Π) ] is equivalent as a PROP to , the PROP for non-counital cocommutative comonoids. We then locate this primitive construction inside the standard cospan/corelation framework: realizes pushout-style gluing as a free hypergraph category; collapses under jointly epic corestriction to , the PROP for extraspecial commutative Frobenius monoids; and the Yoneda envelope [ \mathcal W=(^{op},) ] is a presheaf -topos carrying the standard subobject, modality, and monotone fixed-point apparatus. The PROP-level identification is the only result claimed as new; the remaining material is organizational and reduces explicitly to cited classical results.

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