  We study a simplest viable dark matter model with a real singlet scalar,
vector-like singlet and a doublet lepton. We find a considerable enhancement in
the allowed region of the scalar dark matter parameter spaces under the
influence of the new Yukawa coupling. The Yukawa coupling associate with the
fermion sector heavily dominant the dark matter parameter spaces satisfying the
current relic density of the Universe. Dilepton$+\slashed{E}_T$ signature
arising from the new fermionic sector can observe at Large Hadron Collider
(LHC). We perform such analysis in the context of 14 TeV LHC experiments with a
future integrated luminosity of 3000 ${\rm fb^{-1}}$. We found that a large
region of the parameter spaces can be probed by the LHC experiments. The
projected exclusion/discovery reach of direct heavy charged fermion searches in
this channels is analyzed by performing a detailed cut based collider analysis.
The projected exclusion contour reaches up to $1050-1380~{\rm GeV}$ for 3000
${\rm fb^{-1}}$ for a light dark matter $\mathcal{O}(10)$ GeV from searches in
the $ pp \rightarrow E_1^\pm E_1^\mp, E_1^\pm\rightarrow l^\pm S \rightarrow ll
+ \slashed{E}_T$ channel.
