Kirishima Chikushi, a second-year high school student, is a true introvert who is even looked down upon by underclassmen. He is granted a mysterious skill called 'Rule Ignorance,' but he doesn't know how to use it, leaving him stagnating both as a student and as an explorer. One day, he encounters a famous streamer, Ayatsuki Miru, in a dungeon. Miru, who is streaming the sudden appearances of powerful 'Emergency Monsters' in dungeons, struggles against their overwhelming strength and finds herself in mortal danger! Just as Chikushi tries to intervene and help, his mysterious skill 'Rule Ignorance' awakens!