QP is a manga created by Takeshi Hiroshi along with Crows and Worst. The series is not directly linked to the stories of Crows or Worst but set in the same universe. One example is Hiromi Kirishima being band mates with Naraoka Tsuneyoshi.
Famously known as QP of Bonten High, Ishida Kotori returns to his hometown after a four year absence. Now living an honest life, Kotori is being drawn back from his violent life by a former friend.