  A dynamical mechanism, based on a confining non-abelian dark symmetry, which
generates Majorana masses for hypercharge-less fermions, is proposed. We apply
it to the inverse seesaw scenario, which allows to generate light neutrino
masses from the interplay of TeV-scale Pseudo-Dirac mass terms and a small
explicit breaking of lepton number. A single generation of vector-like dark
quarks, transforming under a $\text{SU}(3)_\text{D}$ gauge symmetry, is coupled
to a real singlet scalar, which serves as a portal between the dark quark
condensate and three generations of heavy sterile neutrinos. Such a dark sector
and the Standard Model (SM) are kept in thermal equilibrium with each other via
sizeable Yukawa couplings to the heavy neutrinos. In this framework the
lightest dark baryon, which has spin $3/2$ and is stabilized at the
renormalizable level by an accidental dark baryon number symmetry, can account
for the observed relic density via thermal freeze-out from annihilations into
the lightest dark mesons. These mesons in turn decay to heavy neutrinos, which
produce SM final states upon decay. This model may be probed by next generation
neutrino telescopes via neutrino lines produced from dark matter annihilations.
