The Delinquent is a member of the Jurals that shows up in Episode 49. He is a boy with spiky black hair and green jumpsuit. He is introduced as a bully who trashed Ken's friends. Ken's classmates ask to help them teach the bully a lesson.
The Delinquent never gives a name but introduces himself by laughing and jumping a motorcycle off a building. He proceeds to punch and hit Ken violently , despite Ken pleading for peace. In order to settle things, the Delinquent proposes they have a motorbike race to determine the winner.
During the race, the Delinquent crashes and seems to have lost. But before he is defeated he reveals he was actually a Jural the entire time! Ken dispatches the Jural and the threat is no more.