The recent three decades witness China's rapid economic development. It is common that white-collar workers have to work overtime. More and more white-collar workers, thus, suffer from "death of overwork" or "depression" due to their frequent overtime working. In recent years, the emergence of some new forms of working overtime phenomena, such as "no pay overtime" or "voluntary overtime", which have greatly affected white-collar workers' quality of life, or even their physical health, draws extensive attention from the academic circles. Among them, the "voluntary overtime work" of the private education institution curriculum consultants cannot be ignored. In fact, there is an unspeakable "forced means" behind all kinds of "voluntary overtime". This study, taking course consultants of a large private IT education institution in T city as subjects and using Michael Burawoy's "making out" theory, Goffman's dramatization theory, and the "caring culture" concept, explores the "overtime" phenomenon of private institutions. The results of the study indicate that 1) when the private enterprise managers formulate the "rules of the game", "background rules" are the root causes of "overtime"; 2) "caring culture" is a reconciliation method to ease the conflicts between the aforementioned rules; and 3) although the "voluntary overtime" phenomenon, in appearance, is an embodiment of employees' dedication to their work, it is actually driven by a whole set of institutional logic behind the phenomenon.