This article aims to describe some of the recurrent stereotypic indexical values that a group of young Cameroonian immigrants in Paris assign to Francanglais, a lexical register of French associated with informal and casual interactions, among young people, in urban settings in Cameroon. I analyse their metapragmatic discourses about this register, which were collected through interviews and based on ethnographic fieldwork in a pan-African association during my PhD research. These discourses are imbued by recurrent ideologies of slang, whereby speech repertoires are evaluated as deviant with respect to one or more presupposed standards when brought under slang formulations (see Agha 2015: 308). Therefore, I show that, through the opposition they make between language and slang, and through the recurrent metaphor of the hood, which is associated with the social figure of the thug, speakers tend to depreciate Francanglais by categorising it as a slang and thus by evaluating it as a substandard variety of the French language. They create symbolic boundaries between different and contrastive social types of speakers (young people vs. grown-up people, boys vs. girls, thugs vs. well-mannered people, rude people vs. polite people, competent French speakers vs. incompetent French speakers), and they associate these personae with contrastive social spaces and values.