store in the apocolypse

Sam is 20 years old man. one day as he was walking in a sunny day a rain started to pour on his head but he decided not to mind it. after a few minutes he was drenched in the rain and in a bit gloomy mood he decided to go to a local shop. he looked to see its name but it was raining too hard. it felt like the weather was doing a payback for those 3 weeks of dry weather. as he was close to the door he slipped on a water puddle and crashed his head to the door. when he waked up he lifted his head and touched the place where he hitted and almost shouted from the pain then he heard a sound. a feminine sound. I will be your guide for your survival. little did he know that it was his system that will make him the last hope for human survival.