Some things we cannot say might be considered nonfiction because they are harsh truths or secrets that society may not be ready to hear. For example, certain historical events that are covered up or ignored. However, in fiction, there can also be unsaid things like the unspoken thoughts and feelings of a character that add depth to the story but are not directly stated.
I'm not certain who the author of 'the things we cannot say true story' is as the title isn't very common in my knowledge. It could be an indie author or someone who wrote it for a very specific audience or purpose.
I'm not sure specifically which 'the things we cannot say true story' you're referring to. It could be about secrets that people are afraid to disclose, or perhaps stories that are so difficult or dangerous to tell that they remain unspoken.
In nonfiction, the things we cannot say are often facts that are inconvenient, dangerous, or violate social norms. For example, whistleblowers may know certain illegal activities in a company but are afraid to speak out. In fiction, the unsaid things are more about creating mystery or emotional depth. A character's unspoken love for another might be left unsaid to build tension.
Without having read the book, it's difficult to name the specific main characters. But in a novel with such a title, we can assume there is a character who has a complex backstory related to the things they do when no one is watching. There could be a love interest or a family member who becomes involved in the discovery or consequences of these actions in the dark. There may also be an antagonist who either causes or exacerbates the situations where these hidden actions take place.
In 'Things We Do in the Dark' novel, the theme of identity is likely present. When people do things in the dark, they might be exploring different sides of their identity that they don't show in the light. It could also touch on the theme of power dynamics. Some characters may use the secrecy of the 'things in the dark' to gain power over others, while others may struggle to break free from those who hold power in these hidden situations.
Typically, in a novel like this, there could be a character who is haunted by their past actions that were done in the dark. Maybe a person who has a mysterious background and is trying to hide it from others. There might also be a nosy neighbor or a detective - like character who is trying to uncover the secrets related to these 'things in the dark' that the other characters are involved in.
One common theme is the struggle between light and dark. Hermione, with the Dark Mark, has to constantly fight against the dark influence it represents. Another theme is forbidden love. Draco and Hermione coming from different sides in the wizarding world makes their relationship a forbidden one, especially with the added complication of the Dark Mark.