Each chapter will be between 30 to 40 minutes long if you read fast, maybe even less.
The game is divided into 3 routes once you finish chapter 5, where you will choose whether to continue the story with the demons, the humans, or the angels. That is, they are not all played at the same time, and from here on it will follow this order:
Chapter 1, 2, 3 and 4 > Chapter 5 ( Route choice) > Chapter 6.1 (Demons) or 6.2 (Humans) or 6.3 (Angels). > etc.
If you play in a linear way, that means only a single route (angels, humans or demons) about 7 hours, without being exact.
But if you want to play all the complete routes, about 14. (For this option, we recommend to have a saved game at the end of chapter 5).
We hope you found it useful!