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Interactions between the extragalactic background light (EBL) and very highenergy {\gamma} rays (VHE; E > 10 GeV) from cosmological sources alter their{\gamma}-ray spectrum. The stronger absorption of harder {\gamma} rays causes asteepening of the observed {\gamma}-ray spectrum at the high energy tail whichcan be expressed by an increase of the power index. The effect provides a linkbetween high energy astrophysics and the evolution of galaxies. In this work wedevelop a new hybrid EBL model by augmenting our previous analytic model withinformation from semi-analytic galaxy catalogues. The model allows us to studythe {\gamma}-ray opacities of individual {\gamma}-ray paths through the(simulated) universe and evaluate the effect of local fluctuations in the EBLintensity along each path. We confirm an order of magnitude fluctuations in thelocal EBL (based on the cumulative light from model galaxy distributions withinspheres of 50 $h^{-1}$Mpc). However, the effect of these fluctuations on theVHE {\gamma}-ray opacity is insignificant due to the overall very smallcontribution of the local EBL to the total EBL. We also investigate the effectwhich a galaxy crossing the line of sight of the {\gamma}-ray source may haveon the VHE spectrum. We find that galaxies with stellar masses of M$ > 10^{11}$M$_{\odot}$ could have significant effect on the {\gamma}-ray absorption. It isunlikely that the observed variation in the spectral index is caused by theproximity of single galaxies to the {\gamma}-ray paths as these are extremelyrare.

Detailed modelling of the EBL along VHE {\gamma}-ray paths