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We consider a simple extension of the Standard Model with a scalar top-philicDark Matter (DM) $S$ coupling, apart from the Higgs portal, exclusively to theright-handed top quark $t_R$ and a colored vector-like top partner $T$ with aYukawa coupling $y_{ST}$ which we call the topVL portal. When the Higgs portalis closed and $y_{ST}$ is perturbative $ (\lesssim 1)$, $TS\to (W^+b, gt)$,$SS\to t\bar{t}$ and $T\bar{T}\to (q\bar{q},gg)$ provide the dominant(co)annihilation contributions to obtain $\Omega_{\rm DM} h^2\simeq 0.12$ inlight, medium and heavy DM mass range, respectively. However, large$y_{ST}\sim\mathcal{O}(10)$ can make $SS\to gg$ dominate via the loop-inducedcoupling $C_{SSgg}$ in the $m_S<m_t$ region. In this model it is the $C_{SSgg}$coupling that generates DM-nucleon scattering in the direct detection, whichcan be large and simply determined by $\Omega_{\rm DM} h^2\simeq 0.12$ when$SS\to gg$ dominates the DM annihilation. The current LUX results can excludethe $SS\to gg$ dominating scenario and XENON-1T experiment may further test$y_{ST}\gtrsim 1$, and $0.5\lesssim y_{ST}\lesssim 1$ may be covered in thefuture LUX-ZP experiment. The current indirect detection results from Fermigamma-ray observations can also exclude the $SS\to gg$ dominating scenario andare sensitive to the heavy DM mass region, of which the improved sensitivity byone order will push DM mass to be above 400, 600, 1000 GeV for $y_{ST}=0.3,0.5, 1.0$, respectively. $T\bar{T}$ pair produced at the hadron collider willdecay $100\%$ into $t\bar{t}+E^{miss}_T$ signal when kinematically open. Thelatest ATLAS 13 TeV 13.2 $\mathrm{fb^{-1}}$ data can excluded $m_T$ between 300(650) and 1150 (1100) GeV for $m_S$ =40 (400) GeV and the exclusion region canreach up to $m_S\sim 500$ GeV.

Top-philic Scalar Dark Matter with a Vector-like Fermionic Top Partner