After graduating from junior high school, DQN boys Horio and Iwashita, who got a job at a local cleaning company, had a fateful reunion at a house they happened to visit one day. "Huh? Could it be that he was the homeroom teacher of Class B? Is that Ryoko-sensei?" A few days after that, a beautiful female teacher, Ryoko, receives a postcard "Information about the class reunion" written in her dumb handwriting...
