Pubescence 4 (2014)

Xiao Yu and Xiao Fei finally got together. Xiao Yu became a criminal police officer, while her ex-boyfriend became a drug dealer. The ex-boyfriend wanted to use Xiaoyu's special status to open up a channel to transport drugs to the mainland, and promised Xiaoyu a high salary. Xiaoyu decides to use this as an opportunity to catch them and even break ups with Xiao Fei to make her undercover story more believable.