Jang Baek-hee suffers from compulsions due to the trauma of domestic violence. One day, as graduation draws closer, he meets Yang Il-woo, who had just transferred schools from Seoul. "I wonder if similar people...

The author, a high-school teacher, recounts his 12 years on "night patrol" in Yokohama City, where he comes face to face with youth dealing with issues ranging from self-mutilation to drug abuse.