Male, 12 years old, 146.4cm, 45kg. He is Cha Do-woon's son and Cha Duri's twin brother, serving as the pilot of Tobot X. Unlike Duri, he is planned, meticulous, and calm. He has a strong sense of duty and sincerity, being gentle and kind to everyone. However, he has a bit of a temper and often raises his voice at Duri. He is very intelligent and excels most at mathematics.

Male, 12 years old, 146.4cm, 46kg. He is the pilot of Tobot Y. He is Cha Do-woon's son and Cha Hana's twin brother, born 10 minutes later, making him the younger one. Unlike Hana, he is playful, active, and childlike, which often gets him scolded by his father. He dislikes Hana acting like the older brother just because of a 10-minute difference, so he refuses to call him 'Hyung'.

Male, 12 years old, 151.2cm. The pilot of Tobot Z and Kwon Limo's adopted son. He enjoys listening to music, plays guitar, is interested in instruments, and always wears a headset. He is chic and doesn't have large mood swings. He is deep-thinking and delicate in caring for others, showing many smiles to his younger brothers and his father. He can be easily swept up in emotions; when truly angry, he becomes agitated and lashes out at his opponent with chilling intensity. He lost his left arm and leg in a past traffic accident, so Kwon Limo personally crafted a prosthetic arm and leg for him. As they were made by Limo, one of Daedo City's top engineers, the modified left limbs boast incredible superhuman strength.

Male, 10 years old. The pilot of Tobot Pop. He lives in the house across from Semo. He is innocent and has a very good relationship with his parents, being a lovable son who acts cute and gives them kisses. He loves and excels at soccer, belonging to the 'Daedo Banana' soccer club at Daedo Elementary. He follows Semo like a real brother, and Duri finds Han-su very adorable.

Male, 10 years old. The pilot of Tobot A and the son of the CEO of the Clover Group conglomerate. He is so timid that it's suspected he has social anxiety, but within that timid personality lies a righteous side. He eventually gained confidence and became close friends with Han-su and On-dal.

Male, 12 years old. The pilot of Tobot W, the only flying Tobot. Due to family circumstances, he once lived apart from his parents in Daedo City, acting as Tobot W's pilot while caring for his sick younger brother. Now, he lives happily with his parents on Gajae Island. There is a large gap between the subjects he excels at and those he struggles with, possessing a STEM-oriented mind. He is good at cooking and has been mature since childhood, making him mentally sophisticated.

Male, 10 years old. Dokgo Oh-gong's younger brother and the pilot of Tobot Twin Punch. He once spent time in the hospital due to poor health, but has now recovered. As a hardcore Tobot fan, he is proud that his brother is the pilot of Tobot W. He is a natural strategist with a remarkable talent for persuading people.

Female, 11 years old. She became the pilot of Steel, Chrome, and Iron through a wristwatch-style Tobot Phone, and serves as the sole pilot of Heavy Metal, the fusion of the three Tobots. A 4th-grade elementary school girl and the granddaughter of Dr. Ma Gak-jin. She has no shyness and makes friends easily, being a self-directed man of action. She remains calm and mature while maintaining high initiative.

Male, 40 years old. Together with his friend Cha Do-woon, he co-developed the first Tobot, Tobot ZERO, and later developed Tobot Z on his own. He lost his wife in a fire 8 years ago, and years later, he treated Kwon Semo, who was injured because of him, and adopted him as his son. He is bright and kind, but shy, with Do-woon being his only friend. He is a doting father with deep affection for his son Semo. Semo is well aware of this side of Limo, trusts him, and considers him his real father; thus, he gets truly furious even at his friends if they insult Limo. He often tries cooking as a hobby, but he is the ultimate kitchen disaster—unable to even peel an apple properly and constantly burning food.

Male, 40 years old. The father of Cha Hana and Cha Duri. A single dad who lost his wife in an accident 8 years ago and has been raising his two sons alone. He is a very gentle and warm father, but one who knows how to get properly angry when necessary. He is the representative of Good-Car Good-Car Center. Due to the fire 8 years ago, he lost his wife and suffered severe leg injuries, becoming physically disabled and using a wheelchair. Perhaps because he has cared for the children alone without a wife, his cooking and housework skills are top-notch.