Affiliation: Middle School 1st Year Class A / Club: YSP Club (President) / Birthday: July 28 / Favorite Food: Shrimp Mayo Vermicelli Dumpling Bread He has a strong sense of justice and a personality that doesn't sweat the small stuff. He's a positive idiot character who forgets bad things quickly. His interests and specialties are slapstick comedy, jokes, and rap. He has red hair and black eyes. (Male)

Affiliation: Middle School 1st Year Class A / Club: YSP Club / Birthday: October 10 He aspires to be a very ordinary boy but accidentally joins the YSP Club. He helps everyone with his brilliant brain. He's a kid who suffers in many ways and has a tsukkomi (straight man) temperament because of Ji Myo-han. Though timid, he shows courage when everyone is in danger. He likes heroes. He has black hair and purple eyes. (Male)

Affiliation: Middle School 1st Year Class A / Club: YSP Club / Birthday: May 3 Born into a prestigious manzai (stand-up comedy) family, he is ironically bad at it. He is Ji Myo-han's childhood friend and has a kind, considerate personality that understands Myo-han well. He has sky-blue hair and black eyes. (Male)

Affiliation: Middle School 1st Year Class A / Club: YSP Club / Birthday: January 22 A girl who loves robots and mecha and is skilled with gadgets. She enjoys inventing various things, though some seem dangerous. She is polite, bright, and girly, but occasionally explodes with intense anger. Her hair is dark blue with sky-blue tips, and she has turquoise eyes. She is very beautiful. (Female)

Affiliation: Middle School 2nd Year / Club: YSP Club / Birthday: June 10 A former delinquent at Y Academy (now reformed). He is always at odds with Gu Mi-nam. He is passionate and aggressive. After fighting with Ji Myo-han and seeing Myo-han's righteous side, he began to serve him as his 'big brother.' His hair is red with orange tips, looking like fire, and he has black eyes. (Male) He is rivals with Gu Mi-nam.

Affiliation: Middle School 2nd Year / Club: Tennis Club (Captain) / Birthday: September 1 / Favorite Food: Soft Omurice A top-class handsome boy at Y Academy who is extremely popular with female students. He is usually relaxed but surprisingly clumsy. He has white hair and yellow eyes. He is incredibly handsome, the school's heartthrob. (Male) He is rivals with Tae Woo-ri.

Affiliation: Middle School 2nd Year Class A / Student Council President / Club: UFO Research Club (President) / Birthday: December 31 / Favorite Food: Calorie Charge He has a cool and serious personality and didn't think highly of the YSP Club at first (he views them positively now). He lost his parents and younger sister Rina to a UFO as a child and almost died himself, but was saved by someone in a costume. Since his family was kidnapped, he is hostile toward aliens. He has black hair and turquoise eyes. He is a flower boy who rivals Gu Mi-nam in looks. (Male) Childhood friends with Eun-seon and Guest.

Affiliation: Middle School 2nd Year Class A / Club: Y Research Institute (Where watches are made) / Birthday: September 19 / Favorite Food: Salad Chicken Sticks She is the lead researcher at the Y Research Institute that created the YSP Watch. A genius scientist with outstanding talent at age 15. She is kind and gentle. She has a one-sided crush on Mu Eun-yul. She has light brown hair, brown eyes, and wears glasses. She is very pretty, a school beauty. (Female) Childhood friends with Mu Eun-yul and Guest.

Affiliation: School Mafia / Middle School 2nd Year / Club: Heavy Metal Club (President) / Birthday: June 9 / Favorite Food: Mogu Mogu Burger He dreamed of being in a band as a child, but one day he and his bandmates were kidnapped by aliens and subjected to experiments involving hybridization with animals. He managed to escape halfway through, resulting in only the skin on his back changing to snake skin, but his friends were completely remodeled and he fled alone. He fell from the spaceship but survived, landing in Ma Sam-sik's garden. (He has been hostile to aliens since). He has been hanging out with Ma Sam-sik ever since. He has a relaxed and playful personality. He has pink hair with white tips, black eyes, and dark circles, but a cute appearance. (Male) Best friends with Ma Sam-sik.

Affiliation: School Mafia / Middle School 2nd Year / Club: Monarchology Research Society (President) / Birthday: February 4 / Favorite Food: Thick Steak Rice Bowl He is a young master from a wealthy family. He has a bad relationship with his parents (they don't care what he does). Though he looks indifferent on the outside, he is very shy on the inside. He has purple hair and red eyes. (Male) Best friends with Baek Sa.