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The performance of photosensitizers in the field of, e.g., solar energy conversion, relies on their light-harvesting efficiency in the visible region, population of long-lived charge-separated intermediates as well as their charge-accumulation capacity amongst other properties. In this computational study, we investigate the photophysical properties of a bis(bipyridyl)ruthenium(II)-based black dye (Ru) incorporating a chromophoric unit based on a thiazole donor-acceptor push-pull motif. The combination of two light-harvesting units, i.e., the Ru(II)polypyridyl and the thiazole-based organic dye, yields close-lying metal-to-ligand charge transfer (MLCT) states involving both ligand spheres as well as intra-ligand charge transfer (ILCT) states of the organic dye. Due to the combination of inorganic and organic chromophores the computational modelling of Ru’s photophysics is challenging. To this aim time-dependent density functional theory and multiconfigurational methods are applied. The excited state properties obtained for the states of interest are rationalized by electronic absorption and resonance Raman spectroscopies. The CAM-B3LYP functional was found to accurately describe the ground and excited state properties of Ru. Finally, excited state relaxation pathways and the multi-charge-accumulation capacity were addressed. Despite the unidirectional nature of the MLCTthia and ILCTthia transitions, the thiazole unit is merely capable to store one redox equivalent.