I will provide some ideas for you to write the 150 words essay.
* It might be said that Labyrinths is used as a metaphor to convey the idea of lost, you might get lost in some hours. It has plenty of symbolic meaning in the story and it is presented in different layers.
Asa physical setting as a garden surrounded by Ts'ui Pen's Pavilion of the Limpid Sun and as a symbolic setting, which uses Yu Tsun´s mind as a maze.
On the other hand, Pen´s novel can be also seen as a labyrinth because it creates parallel and alternatives narratives.