Since I'm not well - versed in Yuta Tanaka's light novels specifically, it's hard to say for sure. But in general, light novels often have simple yet engaging language, vivid characters, and unique story settings. His works might also follow these trends.
Maki in fanfiction usually has a fierce loyalty to her friends, especially Yuta. She is the type to fight for what she believes in. Yuta is sometimes portrayed as being a bit naive in the ways of the world outside his own small circle, but his pure heart makes him endearing. In many stories, their different personalities create an interesting dynamic, like in a story where Maki's boldness gets them into a risky situation and Yuta's calm thinking gets them out.
Expansion usually referred to the expansion, expansion, or extension of the original text to enrich the content of the text, increase the length of the story, expand the plot, and so on. In novel writing, expansion was a common literary technique that could make the story more lively and interesting, allowing the readers to understand the plot more deeply. Expansion could be achieved by adding details, changing the plot order, adding characters, and so on.