班主任就是容嬷嬷的化身
[bān zhŭ rèn jiù shì róng mā mā de huà shēn]
My Class Teacher is the Embodiment of Auntie Rong from Story of Concubine Wu Zetian,' here Auntie Rong (a character from a popular Chinese TV drama) is often strict or disciplinarian. Thus, the username implies that the class teacher is perceived as very strict, demanding, similar to Auntie Rong's personality traits.