Suggest me a 200-400 page book that deals with purpose, the meaning of life, existentialism and stagnation in a witty/lighthearted way. Bonus points for magical realism!

I loved these books –
The midnight library,
The cat who saved books,
If cats disappeared from the world,
Siddhartha,
The alchemist,
Neverwhere,
The miniaturist.

(I’m looking for something that’s targeted more to adults and preferably a stand alone book rather than a series)

by magpiemystic