Attack on Titan: The Harsh Mistress of the City, Part 1

Shingeki no Kyojin: Kakuzetsu Toshi no Joō (Ue) (進撃の巨人　隔絶都市の女王（上）) is a light novel based on the Attack on Titan manga. It is written by Ryō Kawakami and illustrated by Range Murata.

Plot
Shortly after Wall Maria is breached in Shiganshina District, Quinta District in the west falls into chaos with the appearance of the Titans. When all authority is either evacuated or deceased, Rita Iglehaut of the Quinta Garrison takes up the duty of leading the district. In Fuerth District in the western region of Wall Rose, Mathias Kramer, childhood friend of Rita, is determined to ensure that she is brought into safety. With the helping hands of a band of thieves, Mathias and his group set out for the isolated city as Rita maintains ruthless order.

Prologue
Wall Maria is breached and Rita tries to help with the chaos with only half of the population left behind in demise.