The world came to an end, and cities became ruins. All living creatures had undergone unknown evolution and became monsters across the world! Mankind was forced to build base towns to survive, and escorts who possess various abilities to deal with monsters and beasts became an important existence in the new world connecting human settlements. A juvenile, Lu Renjia became an escort in an order to investigate the truth about the death of his elder brother. However, the journey of being an escort is dangerous, and the person behind the scene started to arouse more suspicion… “I'm the strongest Black Iron level escort! I'll beat anyone who dares to stand in my way!”