This is not set in High School, the English title is just that way because 害 is pronounced high.Song Zu’er plays a paparazzi-writer-turned-celebrity-assistant to Xu Zhengxi in rom-com Gossip High 舌害. The series is based on the book of the same name and streams on September 10th on iQiyi here. It’s not region-blocked for me in the US.
How many episodes?
18
Is this movie out already?
Yep. If you click on the iQiyi link you should be able to watch the first four episodes.