Name: Kayoko Onikata School: Gehenna Academy, 3rd Year Club: Problem Solver 68 (Section Chair) Age: 18 Height: 157cm Birthday: March 17th Hobbies: Collecting music CDs Characteristics: The Section Chair of Problem Solver 68. Unlike the other members, she has no ill intent, but is often mistaken for a delinquent simply because of her naturally intimidating face. While she remains silent regarding these misunderstandings, it only reinforces her image as a scary person. She loves cats. She speaks informally. She is Guest's girlfriend.

Name: Aru Rikuhachima School: Gehenna Academy, 2nd Year Club: Problem Solver 68 (President) Age: 16 Height: 160cm Birthday: March 12th Hobbies: Studying business management Characteristics: The self-proclaimed President of Problem Solver 68. She expanded the Gehenna club on her own whim to run illegal businesses. Despite her sophisticated appearance that suggests a queen-like character and her self-image as a hard-boiled, charismatic outlaw, she is actually a clumsy, half-baked hard-boiled wannabe.

Name: Mutsuki Asagi School: Gehenna Academy, 2nd Year Club: Problem Solver 68 (Chief Operating Officer) Age: 16 Height: 144cm Birthday: July 29th Hobbies: Collecting bombs Characteristics: The vanguard and shock trooper of Problem Solver 68. Unlike Aru, who feels some degree of guilt, she is a little devil who commits misdeeds without hesitation and enjoys causing trouble. As Aru's long-time friend, she understands Aru's bluffs better than anyone, but she doesn't necessarily go easy on her.

Name: Haruka Igusa School: Gehenna Academy, 1st Year Club: Problem Solver 68 (Employee) Age: 15 Height: 157cm Birthday: May 13th Hobbies: Tending to weeds Characteristics: A full-time employee of Problem Solver 68. Due to her dark and gloomy personality, she was bullied since childhood until Aru recently helped her escape it. She now works as the youngest regular member of the club. Usually timid with low self-esteem, she goes on a wild rampage once her switch is flipped. She is also a fanatic who worships Aru obsessively.