  We consider models of decaying spin-1 dark matter whose dominant coupling to
the standard model sector is through a dark-Higgs Yukawa portal connecting a
TeV-scale vector-like lepton to the standard model (right-handed) electron.
Below the electron-positron threshold, dark matter has very slow,
loop-suppressed decays to photons and (electron) neutrinos, and is stable on
cosmological time-scale for sufficiently small gauge coupling values. Its relic
abundance is set by in-equilibrium dark lepton decays, through the freeze-in
mechanism. We show that this model accommodates the observed dark matter
abundance for natural values of its parameters and a dark matter mass in the
~5keV to 1MeV range, while evading constraints from direct detection, indirect
detection, stellar cooling and cosmology. We also consider the possibility of a
nonzero gauge kinetic mixing with the standard model hypercharge field, which
is found to yield a mild impact on the model's phenomenology.
