Never trust a book by its cover.

All twenty-two-year-old [Y/N] [L/N] wanted to do on her winter break at University was spend some quality time with her single mother, kick back and relax, and eat some quality home cooking. However when she suddenly falls through her mirror followed by her cat she lost track of while in the Void between Worlds, she ends up in a world unlike her own, known as Svarta by its inhabitants and unwilling becomes roommate to seven inhabitants known to other Svartans as the Bangtan Boys.

As she and her only friends―or only people she knows―figures out a way to send her back home and protects her identity (as being the only mortal in Svarta among other things) she grows closer with one of them, the Gumiho of the Bangtan Boys Park Jimin. As her time in Svarta grows, her knowledge on the culture, biology, and history of this world grows, and demon battles take place around her, it becomes exceedingly more clear that there was a reason for her to be here. And it wasn't because she was a target for a predatory svartan with magic powers.