"Book of Xion", a novel where a high school girl summoned from Japan learns Arka - Arka: One of the Most Developed Conlangs

It is a novel where a high school girl, Xion, summoned from Japan learns Arka in Arbazard.
Haven't you ever thought that it is strange (or too expedient) that personages learn language(s) of aliens by magic or something in science fictions?

In "Book of Xion", expedient magic or apparatus with which personages learn alien's language(s) don't show up. Xion starts learning Arka from scratch.
No one has written such a "realistic fantasy" before "Book of Xion" in Japan.
You can read "Book of Xion" here.
You can buy "Book of Xion" here.

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