She is a talented and beautiful girl who works as a substitute teacher in her mother's school because her mother wants to spend her honeymoon with her father. On the first day at school, she got into trouble with a difficult young master. All stories begin with the phrase "that classmate, please stop"...
She was hurt because of love and turned into the top killer "Bing Po". During another mission, her opponent turned out to be him. She chose to continue completing the mission...