Totsukuni no Shoujo

The Girl From the Other Side: Siúil, a Rún (とつくにの少女) is a manga series by Nagabe. It is serialized in Comic Garden. Seven Seas has licensed it for English release.

Plot
Once upon a time...

In a land far away, there were two kingdoms: the Outside, where twisted beasts roamed that could curse with a touch, and the Inside, where humans lived in safety and peace. The girl and the beast should never have met, but when they do, a quiet fairy tale begins.

This is a story of two people—one human, one inhuman—who linger in the hazy twilight that separates night from day.