  We extend the Dirac Scotogenic model with the aim of realizing neutrino
masses together with the mass of a keV-scale dark matter (DM) candidate via the
same one-loop topology. Two of the Standard Model (SM) neutrinos become massive
Dirac fermions while the third one remains massless. Our particle content is
motivated by an anomaly free $\text{U}(1)_\text{B-L}$ gauge symmetry with
exotic irrational charges and we need to enforce an additional $\mathcal{Z}_5$
symmetry. The dark matter candidate does not mix with the active neutrinos and
does not have any decay modes to SM particles. DM is produced together with
dark radiation in the form of right handed neutrinos via out of equilibrium
annihilations of the SM fermions mediated by the heavy B-L gauge boson. In
order to avoid DM over-production from Higgs decays and to comply with
Lyman-$\alpha$ bounds we work in a low temperature reheating scenario with
$4\;\text{MeV}\lesssim T_\text{RH}\lesssim 5\;\text{GeV}$. Our setup predicts a
contribution to $\Delta N_\text{eff.}$ that decreases for larger DM masses and
is below the sensitivity of upcoming precision measurements such as CMB-S4. A
future observation of a signal with $\Delta N_\text{eff.}\gtrsim 0.012$ would
exclude our scenario. We further sketch how inflation, reheating and
Affleck-Dine baryogenesis can also be potentially realized in this unified
framework.
