Sukuna does die in the manga. The way it happens is quite dramatic and ties in with many other elements of the story, adding depth and tension to the overall narrative.
One common theme could be the exploration of the relationship between Shinra Kusakabe and another male character, such as how they overcome obstacles together. Another might be their mutual understanding and support in a challenging world.
Nope. Ryomen Sukuna has no basis in reality. It's a product of the creative minds of the writers and illustrators who designed a captivating fictional character for the enjoyment of the audience.
The novel 'On Hand of God by Yo Kusakabe' is likely to be a very interesting piece of work. Since the title mentions 'Hand of God', it could potentially revolve around themes of fate, divine intervention, or the search for a higher purpose. However, without having read it, it's hard to say exactly what the story is about. It could also explore the characters' personal beliefs and how they interact with this concept of the 'Hand of God'.
In the manga, Sukuna doesn't possess all 20 fingers. There are specific story arcs and events where his finger count changes based on the plot developments.