Cosmetic composition (I) comprises, in an aqueous medium, at least a protective agent of keratinous fibers, at least an aromatic alcohol and at least an aromatic carboxylic acid or its salt. Independent claims are also included for: (1) a process of coloration of keratinous fibers (particularly hair), comprising applying, to the fibers, a direct or oxidation dyeing composition to develop color, and optionally after rinsing and drying, applying (I) immediately or remotely, where application of (I) can be repeated between two colorings and (2) a multi-component coloring agent comprising at least a first component comprising a direct/oxidation dyeing composition and a second component comprising the post treatment composition (I).