In episode 19 of Toaru Kagaku no Railgun S, Saten is shown reading a book to Febri, presumably as a bedtime story.
Transcribed:
国の中央部には、立派すぎる建物が並んでいました。
豪華な化粧石をふんだんに使った、どっしりとした石の建築物です。必ず尖った屋根や、装飾でついている変な生き物の石像が目立ちます。整った区画の中に、それらは丁寧に並んでいました。
道路は車なら十台ほどが並んで走れそうな幅で、きれいに十字に交差しています。薄い土埃を上げながら走るモトラドがとても小さく見える、壮大な都市部でした。
そして、そこには誰もいません。車も走っていません。
エルメスを止めて交差点の中央に立ったキノが、視線と体をぐるりと回します。
「…………」
建物は音もなく磧へと流れていき、また別の建物が現れ、また流れていきます。その向こうには、変わらない蒼い空があるだけなのでした。
Loosely translated:
In the heart of a certain country, there stood buildings altogether too splendid.
They were built from solid stone, much of which was beautifully decorated. They invariably had peaked roofs and stone figures of strange animals that drew the eye. They stood side-by-side in an orderly manner, within their orderly city blocks.
The roads were so wide that ten cars could drive in parallel, and they intersected at perfect right angles. Vehicles would kick up a thin cloud of dust as they drove. They were tiny by comparison with the grandeur of the city.
And there was nobody there. Neither people nor vehicles.
Kino stopped his Hermes in the middle of an intersection and looked all around.
"..."
The buildings silently flowed towards the waterfront as new buildings emerged to take their place, and then those new buildings too flowed away. Beyond them was nothing but the unchanging blue sky.
The first line does not appear anywhere on the internet, so it doesn't look like this is pre-existing Japanese fiction. It could be pre-existing non-Japanese fiction that has been translated into Japanese for the first time (or differently) by somebody involved in the production of Railgun S. Alternatively, it could be original Japanese fiction.
