  Leptoquarks are hypothetical new particles, which couple quarks directly to
leptons. They experienced a renaissance in recent years as they are prime
candidates to explain the so-called \textit{flavor anomalies}, i.e. the
deviations between the Standard Model predictions and measurements in $b\to
s\ell^{+}\ell^{-}$ and $b\to c\tau\nu$ processes and in the anomalous magnetic
moment of the muon. At the one-loop level these particles unavoidably generate
effects in the purely leptonic processes like $Z\to\ell^{+}\ell^{-}$,
$Z\to\nu\bar\nu$, $W\to\ell\nu$ and $h\to\ell^{+}\ell^{-}$ and can even
generate non-zero rates for lepton flavor violating processes such as $\ell\to
\ell^{\prime}\gamma$, $Z\to\ell^+\ell^{\prime -}$, $h\to\ell^+\ell^{\prime -}$
and $\ell\to 3\ell^\prime$. In this article we calculate these processes for
all five representations of scalar Leptoquarks. We include their most general
interaction terms with the Standard Model Higgs boson, which leads to
Leptoquark mixing after the former acquires a vacuum expectation value. In our
phenomenological analysis we investigate the effects in modified lepton
couplings to electroweak gauge bosons, we study the correlations of the
anomalous magnetic moment of the muon with $h\to\mu^{+}\mu^{-}$ and
$Z\to\mu^{+}\mu^{-}$ as well as the interplay between different lepton flavor
violating decays.
