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Let (X, τ ) be a topological space and let τh(X) denote the topology formed by its h-open subsets. We introduce hD-spaces as those spaces in which every nonempty h-open set is h-dense and study them systematically through the associated space (X, τh(X)). The basic observation is that (X, τ ) is an hDspace if and only if (X, τh(X)) is a classical D-space in the sense of Levine, equivalently a hyperconnected space. This yields intrinsic open- and closed-set characterizations and gives preservation and reflection results under natural classes of mappings. We show that every hD-space is a classical D-space, while the converse fails, and we provide an explicit infinite nontrivial hDspace. In contrast, every finite nonempty hD-space is a singleton. We also construct a nontrivial hD-space which is h-T1 but not h-T2, showing that h-T2 is the sharp separation threshold for triviality within the standard h-Ti hierarchy. For subspaces we distinguish τh(Y ) from the trace τh(X)|Y and obtain hereditary results under h-subspace compatibility. For products we establish an exact transfer theorem under h-product compatibility and, using the previously established Hausdorff compatibility result, derive the corresponding consequence for arbitrary families of Hausdorff spaces. Finally, we clarify the position of hD within the h-separation hierarchy and obtain constant-map consequences for Hausdorff targets.