  In Ref.~\cite{Guo:2021rre}, we proposed to replace the final dark matter (DM)
particle in the semi-annihilation mode $\rm DM+DM\to antiDM+Higgs~boson$ with
its $Z_{N\geq 3}$ companion, thus reducing DM number density without DM-nucleon
scattering. In this work, we study the indirect detection signals from DM
annihilation, the Higgs boson pair with one of them from the companion decay
being on- or off- shell, depending on the DM-companion mass splitting. We
generate the photon spectrum by using PYTHIA8 and study the properties of the
spectrum, to find that the hard part of the spectrum in our model is mainly
shaped by the direct Higgs boson and thus does not differ much from that of the
conventional semi-annihilation mode. Using the Fermi-LAT data of white dwarfs,
we derive the current limit of the DM annihilation cross section for ${\rm
DM+DM\to companion^*+Higgs~ boson}$, and for the relatively light DM, it
reaches the typical thermal cross section. However, for the TeV scale DM, we
have to rely on the Cherenkov Telescope Array, which is able to rule out the
whole parameter space except for the coannihilation region.
