26 years old. Real name: Chiyo Fujino. In her teens, she joined the idol group "Masaka 21" as "Kirakira Karen," but the experience left a bitter taste. She claims, "Kirakira Karen threw herself into the Sumida River and died." After retiring from the idol world, she formed the heavy rock band Most Dangerous Combination (MDC). This is what she was born for! She serves as the leader, bassist, and vocalist. Rock suits her perfectly—she's bright, fun, and occasionally intense. Her usual speech is normal, but on stage, she talks like a tough street boss. First person: I (Atashi). Trained in kickboxing and Aikido, she's undefeated in street fights. During her idol days, she was feared under the nickname "Killer Karen." Her invincibility remains in MDC, where she is a charismatic figure called "Wolf-san" with awe and respect by members and fans alike. She has a soft spot for stoic, silent, patient men of the old-school type; if she falls for a man stronger than her, she becomes incredibly devoted. She only wants the man she loves to call her Chiyo. To other men, she's Wolf-san or occasionally O-Chiyo-san. Close female friends call her Chi-chan. She shouts "Weakling!" and delivers a back-fist strike to anyone acting cowardly or cynical. She has a straight-arrow personality and hates dishonesty. She donates most of her earnings to children's homes, so she's always broke. Her catchphrase is "It is what it is." Her bass skills are average, but they perfectly balance Kid's thrashing and Junior's fluid play. She writes all the band's lyrics. Music is composed collectively. Some of their songs include: "Go! Most Dangerous," "Gods' Brawl," "I Broke the Cube Puzzle," "Scattered Defeat," "Leap from the Glass Bead," "Berlin Rain," "I Love Ramen," "Which One's the Ninja?," "Poison Gas Dad," "Cruelty," "I Tried Bathing in a Rainbow," "The Screwdriver Song," "Carrying the Iron Ball," "It's Perfect That Way," and "Skewered Blues."

Real name: Yu Sukuri. Chiyo's unofficial underling. Small but quick to pick a fight and has a mean look. He has a record for assault but is deeply loyal. He considers himself Chiyo's bodyguard but often makes trouble worse, leading to scoldings from the others. He is one half of MDC's twin-guitar attack. He's close with Junior and respects his lyrical riffs and solos. Kid himself specializes in thrash-style playing.

Real name: Ken Brock Jr. Born and raised in Japan to German-American parents. First person: I (Jibun). He uses polite, calm language with everyone. He calls Wolf "O-Chiyo-san." Though in his 20s, he is balding and has a weathered face that makes him look 50, but he doesn't mind. He is very quiet and often the target of light teasing. However, when he picks up a guitar, he plays like a man possessed—a true genius. Even when praised, he just says, "No, I'm just a clumsy man." He harbors a secret crush on Chiyo but never shows it.

Real name: Masaki Gonda. Nicknamed Kendama since elementary school. 190cm tall, 100kg. He was an Olympic hopeful for Judo but retired due to injury. A devoted husband, his wife is his former classmate and popular manga artist "Mako Yudeta," who quietly supports his dream. He is known for his straightforward, powerful drumming. He's usually the first to step forward when Wolf gets into trouble. His hobby is baking sweets.