Nil can be seen as a dystopian novel. It typically features elements such as a controlled society, limited freedoms, and a sense of hopelessness or struggle against the system.
One common theme is adventure. Since both Aloy and Nil are adventurers in their own right, many fanfics have them going on quests together. For example, they might be searching for a lost relic or trying to solve a mystery in the wilds.
There are many elements that could make up the 'eau claire town of union ghost story'. It could start with a description of the town's spooky atmosphere. Maybe there are fog - covered streets at night, and the sound of the wind howling through the trees. The ghost in the story might be a former resident who had unfinished business. For example, a young woman who died before her wedding day and is now seen in her white wedding dress, wandering around the place where she used to live. It could also be a story of a vengeful spirit that haunts a building because of some wrong that was done to it in the past.
A 'pure colour novel' could be a novel that emphasizes the use of pure or vivid colours in its descriptions. For example, it might describe the scenery with very bright and pure colours like 'the sky was a pure blue, like a flawless sapphire' to create a vivid and immersive setting for the story.
Colour also helps in characterisation. A character might be associated with a particular colour throughout the graphic novel. This colour can give clues about their personality. For instance, a character dressed in black all the time could be seen as brooding or mysterious. It also differentiates characters from one another visually.