Yomawari Sensei

Yomawari Sensei (夜回り先生) is a manga series written by Mizutani Osamu and illustrated by Tsuchida Seiki. It was serialized in Ikki. There is a sequel manga series under the name Yomawari Sensei Tokubetsu-hen: Sayonara ga Ienakute (夜回り先生 特別編 さよならが言えなくて).

Plot
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 issues ranging from self-mutilation to drug abuse.