Yami Baito Saki wa Isekai Deshita

If you want to survive, you need to earn money! When his parent becomes ill, high school student Hashiba Ryuuji is forced to abandon his aspirations and take a job to help pay for his mother's hospital expenses. One day, Ryuuji discovers a part-time position that offers an astonishing salary, and despite his suspicions, he decides to take it in hopes of chasing his dreams once more. Following the directions given by his employer, he steps through a mysterious door and unexpectedly finds himself in a strange world where he is suddenly confronted by monsters...!?