Totsukuni no Shoujo

A world is divided into two parts, the Inside and the Outside, with a strict warning against crossing between them due to a curse. Shiva, a girl living in the Outside, resides in an abandoned village with a guardian referred to as “Teacher,” who is described as demonic. Despite being forbidden from physical contact, a connection exists between them. Shiva eventually leaves Teacher to search for her grandmother, which leads to the revelation of the truth about her unusual living situation.