Seven Days War

Quiet, shy high school student Mamoru Suzuhara is devastated by the revelation that his crush, Aya Chiyono, is moving away with her family. However, having found the courage to ask her to run away with him, the pair - together with some of their other classmates - make the decision to escape to camp in the abandoned Satomi Coal Factory nearby. But the fun times of this adventure of rebellious independence may be about to take a worrying turn, as it seems that aren't alone in the factory...