最讨厌班主任占课
[zuì tăo yàn bān zhŭ rèn zhàn kè]
This username directly translates to 'Hate Teacher Advisor Taking Over Classes'. Many students have a common experience in China where class advisors (teacher responsible for all aspects of a class) may take over other subjects' classes, often making students frustrated. This is usually because these teachers may need extra teaching hours or think their course more important, which led this phrase to represent student's dissatisfaction towards it.