Given the exponential proliferation of mobile devices and broadband services, there is a pressing need to amalgamate multiple technologies accommodating infrastructural changes for meeting the ever-increasing demands of user capacity. Therefore, in this paper, we propose the integration of proximity-based direct device-to-device (D2D) communication with the network densification concept. In this paper, we consider user-centric non-overlapping clusters associated with the closest access point for serving user equipment (UE) in the downlink under limited availability of orthogonal resource blocks (RBs), while the D2D links also reuse these downlink RBs. We analytically derive the coverage probability as well as the average transmission rate of D2D links under the proposed model, which results in a complex interference scenario. The performance results verify that our analytical results closely match with simulations for different parametric settings. The impact of the presence of D2D links on the coverage probability of the UEs is also quantified, revealing that the UEs' performance is only modestly affected under the proposed system model. © 1967-2012 IEEE.