Sepian

Jan-yuri gets herself trapped outside Heron, the last city of humans, during a school trip to the force-field that makes the city invisible from the rest of the world. With no way to return, she has no choice but to seek help from the nearest elven village.

Jan tries to find a way back to Heron but the races of Ianoth had banded together to destroy the humans in the War of the Red Valley so Jan's appearance caused mixed feelings amongst them. Who is trustworthy and who is trying to get into Heron to destroy the remnants of humanity?

Just a cellphone novel.