The present work deals with the mechanical characteristics and deflection responses of novel partially biodegradable hybrid composites embracing an animal based (Human Hair), a plant based (Luffa Cylindrica) fiber (denoted as HHF and LCF) and Incense Stick Ash (ISA) under different loadings. Ultrasonicator assisted hand lay-up technique has been followed for the inhouse fabrication process by incorporating epoxy resin as the matrix material while varying weight ratios (0, 5, 10, 15, and 20 wt.%) of ISA filler. Firstly, the density, elastic properties through non-destructive Impulse Excitation Technique (IET), microhardness, strengths under tensile, bending and impact loading are obtained and the surface morphology of fractured surfaces is studied. The composite filled with 10 wt.% ISA shown the best overall tensile, bending and shear properties, while the highest flexural strength and microhardness is depicted by composite filled with 20 wt.% ISA. Subsequently, finite element (FE) analysis using a simulation model in ANSYS is employed to acquire the tensile and flexural strength, those are found to be comparable with the experimental values. Finally, a higher-order nonlinear FE model is developed and implemented using MATLAB programming platform to compute the static responses under different loads (point load, sinusoidally distributed line load, uniformly distributed line load, uniformly distributed load and sinusoidally distributed load) using the experimentally obtained composite material properties. The validity of the developed model has been tested by comparing the results with the data acquired through lab-scale experimentation. From the numerical illustrations, moderate ISA filled (10 wt.%) composites with higher aspect ratio and lower thickness ratio are observed to provide more significant resistance to deflection under static loading.