" Forest of Fireflies " was a very touching Japanese anime that was hailed as one of the four most tear-jerking Japanese comics. There were many reasons why this work was so popular. The Forest of Fireflies tells the story of the young girl Ah Yin and the young boy Ah Zhu meeting and accompanying each other in the forest. The anime's style was fresh and natural, and the setting was very beautiful. It made people feel like they were in a beautiful fairytale world when they watched it. The plot was touching, especially the delicate description of the relationship between Ah Yin and Ah Zhu, which made people deeply feel the sincere feelings between them. The story of Forest of Fireflies was philosophical about the relationship between man and nature. This work emphasized the importance of environmental protection and the treasure of natural resources, making people deeply aware of the importance of harmonious coexistence between man and nature. At the same time, it also expressed people's grief and longing for their loved ones and friends, which resonated and touched people when they watched it. The background music of Forest of Fireflies was also very outstanding, especially the theme song, Light of Fireflies, which was very moving and made people more immersed in the story when they watched it. To sum up, the reason why Forest of Fireflies was so popular was that it was not only an excellent animation work, but also a work rich in philosophy and emotional content. It could arouse the audience's resonance and thinking, and make people have deep feelings and experiences.