  We study the dark matter phenomenology of Standard Model extensions
addressing the reported anomaly in the $R_K$ observable at one-loop. The
article covers the case of fermionic singlet DM coupling leptophilically,
quarkphilically or amphiphilically to the SM. The setup utilizes a large
coupling of the new particle content to the second lepton generation to explain
the $R_K$ anomaly, which in return tends to diminish the dark matter relic
density. Further, dark matter direct detection experiments provide stringent
bounds even in cases where the dark matter candidate only contributes a small
fraction of the observed dark matter energy density. In fact, direct detection
rules out all considered models as an explanation for the $R_K$ anomaly in the
case of Dirac dark matter. Conversely, for Majorana dark matter, the $R_K$
anomaly can be addressed in agreement with direct detection in coannihilation
scenarios. For leptophilic dark matter this region only exists for $M_\text{DM}
\lesssim 1000 \, \mathrm{GeV}$ and dark matter is underabundant. Quarkphilic
and amphiphilic scenarios even provide narrow regions of parameter space where
the observed relic density can be reproduced while offering an explanation to
$R_K$ in agreement with direct detection experiments.
