  We demonstrate a common origin for high-scale leptogenesis and three-loop
neutrino mass generation. Specifically we extend the standard model by two real
singlet scalars, two singly charged scalars carrying different lepton numbers
and two or more singlet fermions with Majorana masses. Our model respects a
softly broken lepton number and an exactly conserved $Z_2^{}$ discrete
symmetry. Through the lepton-number-violating decays of the real scalars and
then the lepton-number-conserving decays of the charged scalars, we can obtain
a lepton asymmetry stored in the standard model leptons. This lepton asymmetry
can be partially converted to a baryon asymmetry by the sphaleron processes.
The interactions for this leptogenesis can also result in a three-loop diagram
to generate the neutrino masses. The lightest singlet fermion can keep stable
to serve as a dark matter particle.
