Rob, the hero, wanted to escape this sadness because of his mother's death, so he moved away from home and came to a strange city. His father is introverted and doesn't like to express his feelings and suppress them. Rob even locked his mother's thoughts in a suitcase, which was not easy to open, and he was often bullied by two classmates at school, so he hated going to school until one day he suddenly found a tiger in the forest of his boss Bo Xiang Bo when he was wandering. Suddenly, I have a strange feeling in my heart. Then I met Sistine on the school bus. The girl was brought to this city by her mother because her parents divorced. She was unpopular at school and was bullied by her classmates on the first day of school, so Rob actually came to the rescue. Rob and Sistine were bullied, Rob kept on forbearing, and Sistine struggled. Later, because of a rash, Rob was advised by the headmaster to go home and rest. So Rob began to help in the place where his father worked and met a woman who also worked for the boss. She told Rob that the problem with her leg was because sadness was on her leg. When she saw Sistine, she said she was full of anger, which crackled on her like lightning. Sistine told Rob about her family from the beginning. Her father was having an affair, so she and her mother moved here. She asked Rob about him. Rob didn't mention anything, and Sistine was very angry. Later, Rob opened his emotional suitcase and told her that his mother had passed away. So Sistine comes to give Rob homework every day. Rob slowly opened the tightly pressed suitcase and told Sistine about the tiger. Although Bo Xiang Bo has a tiger, he is afraid of it, so he asks Rob to help him feed it, and he can't tell anyone. Sistine knew that the tiger would be released, but Rob didn't agree. He thought that if he let the tiger go, he would lose it, but he still wanted the tiger to be free. Sistine told Willy May about the tiger, and Willy May told them that the tiger could not be released because she once released a bird and was beaten by her father. Later, he later, Rob finally decided to let the tiger go, because Sistine said he was a coward, so they let the tiger go and watched it go. But soon, they heard gunshots and saw William and his father, and the dead tiger. Rob went crazy and cursed his father. That is my tiger. How can you kill it? I hate you. I'd rather die because I need her, Caroline, my mother. At this point, Rob finally opened his locked suitcase, and his father opened his heart, saying that although I was in pain, even mentioning this name, I would mention her for you, but she couldn't come back. Now we only have each other. They held a funeral for the tiger, Sistine recited poems for the tiger, and his father asked Rob to admit to Bo Xiang Bo that he had let the tiger go. His father admitted that he killed the tiger and they might lose their jobs. You can also pay for Bo Xiang Bo's works. Rob is at school, because there is a Sistine in the school, so the end result is that everyone opens their hearts and starts an active life.