I'm not sure. It could be based on real events, but it might also be fictional. You'd have to do some research or check the author's notes to know for sure.
Well, in Ian Rankin's Rebus novels, one characteristic is the intricate plotting. The stories keep you guessing until the end. Regarding the 'long shadows' part, it might imply that the past actions of characters, like Rebus's own past mistakes or the history of the city, constantly influence the current investigations. And the setting of Edinburgh is almost like another character, with its alleys and different social strata adding depth to the novels.
As I don't know the details of the 'filosofi kopi' novel, I can't say for sure. But given the name, themes could potentially include coffee culture and philosophy.
One well - known rebus novel is 'The Da Vinci Code' by Dan Brown. It contains various puzzles and symbolic elements that are like rebuses throughout the story.
Look for any hidden meanings or associations. For example, if there's a small egg symbol near a big monster, it could imply that the monster hatches from eggs or is related to protecting its eggs. Pay attention to the position and combination of the elements in the rebus.
The 'filosofi kopi' might be a relatively unknown novel to me. However, generally, a synopsis would include the main characters, the central conflict or theme, and perhaps a bit about the setting. Without having read it, it's hard to be more precise.