They
Nothing has to be read in order and no volume depends on another — but they are all happening in the same world, and now and then that shows.
A name is said in one book that belongs to another. An institution comes up as though everyone already knows what it is. None of it is explained, because to the people saying it there is nothing to explain.
Danny
He turns up doing a job he does not look settled into. He drops things. He apologises. People forgive him, which may be the whole of his talent.
Mrs. Chen
She keeps a shop. Which shop depends on where you are — flowers, tea, something stronger, congee at one in the morning — and she is never surprised to see you. She will say one thing you find yourself thinking about later, and then go back to what she was doing.
Nothing in the plot turns on either of them, and no book asks you to have met them before. That is the arrangement. What they say and do may change this world. It may not. If you notice, you notice.