The beginning is dull and the ending is tragic.
He woke up in a dark corner of the library.
He had just fallen asleep the moment he woke up.
So in fact he is living in a dream.
In this so-called dream, he discovered something---
There are some things that he is afraid of losing but knows he will lose. When he finally loses them, he is not completely lost - in fact, he is relieved.
After feeling relieved, he suddenly wanted to chase her back, but as he chased, he lost track of where the road was. He didn't know why he wanted to chase. He didn't even know what he was chasing.
Then he just wanted to find a place to have a good sleep.
Then he discovered:
He woke up just as he fell asleep.