Panty Flash Teacher - Season 1

Natsukawa Machiko returns to her hometown to take up a teaching position. On her first day, she encounters a group of delinquent students on her commute and is harassed by them. She escapes to the school, only to discover these same students are in the class assigned to her. The harassment resumes until another student, Uoi, intervenes. It is later revealed that Uoi is actually the leader of the delinquent group.