Reborn as an A-Rank Guide: Trapped By The Crazy Sentinels

[Mature content] Having suddenly died from stress, Bunny awakens in the body of an A-rank Guide, only to discover that she has been assigned to District 616—a barren wasteland at the edge of the Federation, where mutated monsters roam beyond the borders. It should have been a simple assignment... Except the three Guides stationed there before her all died under mysterious circumstances. After years of abandoning the district, the Federation has finally decided to send another Guide to the isolated Sentinel Tower, deep in the endless sea of dust and sand, completely cut off from civilization. And the Sentinels stationed there? Everyone says they're vicious mad dogs, shameless perverts, and complete lunatics; men who are constantly teetering on the edge of losing control, their minds consumed by mania and madness. Bunny thought those were just exaggerated rumors meant to scare her. Until she arrived. Because somehow… It was actually a lot worse. — Description from novelcodex.org