I'm not sure specifically what 'kijin gentoushou light novel' is about as it might be a relatively unknown or niche title. It could potentially be about a unique fantasy world with its own set of characters, magic systems, and storylines.
You might try looking for it in specialized light novel stores. Some big bookstores that have a wide selection of international and niche literature could also carry it.
The Yakuza games story portrays Yakuza culture in several ways. It shows their hierarchical structure. The higher - ups have great power and respect, and the lower - level members have to follow strict rules. Also, their sense of justice within their own world is depicted. They have their own way of dealing with disputes and traitors which is part of their unique culture.
I'm not entirely sure as it's not a widely known mainstream novel. It might be about some sort of magical or reverse reincarnation story with elements of romance involving kijin (which could be some sort of supernatural beings).
Sasuke's sharingan would give him a huge advantage in the Yakuza world. He could use it to read the intentions of his enemies, predict their moves during fights or negotiations. Sakura's super strength and medical skills also come in handy. Her strength can be used in combat situations against Yakuza thugs, and her medical skills can be used to treat any injuries they might get during their Yakuza - related adventures.
One of the best yakuza stories is about loyalty within the yakuza clans. For example, there are tales of yakuza members who would sacrifice themselves to protect their bosses. They consider honor and loyalty above all else, and these stories often show how they adhere to a strict code of conduct even in the face of danger.
One of the well - known best yakuza novels is 'Tokyo Underworld' by Robert Whiting. It delves deep into the seedy underworld of the yakuza in Tokyo, showing their power struggles, criminal activities, and the complex web of relationships within the organization. Another great one could be 'Out' by Natsuo Kirino. Although not strictly a traditional yakuza - centric novel, it involves elements of the criminal underworld where the yakuza operate, and it's a very gripping story of women involved in a crime related to the yakuza world. Then there's 'Six Four' by Hideo Yokoyama which also touches on the yakuza influence in Japanese society among other complex themes.