Private tutoring is one of the unintended outcomes of high-stakes testing and has become a widespread global phenomenon. It is called shadow education because it mimics the mainstream curriculum. From the critical perspective, this study investigated the role of private tutoring in a context of high-stakes testing through Interpretative Phenomenological Analysis. It explored 18 Secondary Six (Grade 12) students' reflections on their learning experiences in private tutoring in Hong Kong for one year. Conceptualized with Freire's "Pedagogy of the oppressed," the findings reveal that while students are being oppressed in the washback of high-stakes testing under neoliberalism, shadow education further oppresses the students by (1) intensifying the "banking" concept of education, (2) teaching as the "authority", (3) emphasizing performativity and (4) offering "false generosity". The findings provide implications for potential educational change in contexts where education systems increasingly rely on accountability and selection through high-stakes testing. By problematizing the role of private tutoring through the conceptual lens of oppression, the study calls for research to take a closer look at the impact of shadow education on learners' experiences in the current neoliberal era.