He Yan originally thought that hell should be boundless darkness, just like the deep seabed, suffocating and drowning. She has not been happy at all in the past few years since Shen Mu left. When she wakes up, she returns to her fifteenth year. At this time, Shen Mu is still the melancholy and introverted young man who likes flowers and plants. Xu Ling is still her neighbor's brother who has never turned against her. Everything is still too late, everything is still too late.
Concept: Mutual salvation between male and female protagonists