A Chinese graphic novel.

From the publisher:

After the protagonist of this book, Li Xiaoli, said "Stop" to the person who was inflicting violence at school, she became the target of bullying by everyone in the class. After transferring to another school, she could not get out of the haze in her heart and dared not make friends until she accidentally found a mysterious letter in the drawer. Li Xiaoli found more letters according to the clues of the letters, and after meeting many people and things full of kindness, she finally understood the gentle intentions behind these letters. The way to stop violence is courage, and the best medicine to heal scars is gentleness. Xiaoli insisted on her courage, gained the most sincere kindness of her friends, and walked out of the haze.