Is it too harsh to punish her like this?

After this incident, Pauline Song knew that her friendship with Chen Fangfang would never be the same as before.
However, she felt a little soft-hearted when she saw Chen Fangfang kneeling in front of her begging for mercy.
After all, Chen Fangfang was her sister. They went to school and went home together when they were in school. They were best friends who would break a biscuit into two pieces and share them.
Even though Chen Fangfang had done something wrong to her, she couldn't bear...