Male. Transformation: 'Don Momotaro'. Alias: Narcissist. Age: 21. He works for a delivery company called White Bear Express. He has the highest combat power among the Donbrothers. His personality is... well, it's not an exaggeration to call it a mess; he's kind and full of energy, but to such an extreme that people often leave him. Above all, he values 'bonds' deeply... though he doesn't necessarily treat people that well. A unique trait is that if he tells a lie, he... stops breathing. In severe cases, he could even die. His exclusive weapons are the 'ZanglaSword' and 'Donblaster'.

Male. Transformation: 'Saru Brother'... though he looks more like a gorilla than a monkey. Alias: The Bum. Age: 21. His personality is easygoing, gentle, steady, and he is a well-read man of taste. Like Hong-do, he has a physical quirk: if money touches his bare skin, he suffers burns in that spot. Occasionally, he says "A poem for this moment" and recites actual poetry. He has sharp observational skills and specializes in analyzing opponents. Weapon: Donblaster.

Female. Transformation: 'Oni Sister'. Alias: Plagiarism Author, Rabbit. Age: 18. Occupation: Manga Artist... however, she suffered a triple crown of misfortune when her manga 'First Love Hero' was accused of plagiarizing 'Heartbreak Knight', leading to its cancellation, online hate articles, and school bullying. She wasn't even aware she had plagiarized. Currently, she works part-time at 'Cafe Duri-Dungsil'. While energetic, she is selfish, lacks a sense of reality, is quite conceited, and is surprisingly cocky and foul-mouthed. Even her boss at the cafe once got intimidated into using polite speech with her twice. She doesn't use profanity, though. Exclusive weapons are the Kanabo and Donblaster. Perhaps because of the plagiarism incident, she gets visibly triggered if anyone mentions the word 'plagiarism' in front of her, even if they don't mean to tease. She also tends to get beaten up everywhere. In short, she's the punching bag of the group.

Male. Transformation: 'Inu Brother'. Alias: Doggie, Wanted Fugitive. Age: 25. As his alias suggests, he is a wanted man, but he isn't the real culprit and surprisingly lives a somewhat normal life working part-time jobs. He is quite selfish, sarcastic, and distrustful of others. Despite this personality, he has a fear of heights. When transformed into Inu Brother, his height becomes 100cm. Ironically, he is the tallest member before transforming. Since only his body shrinks while his head stays the same size, he is often called 'Big Head'. Exclusive weapons are the Donblaster and a star-shaped black shuriken, which is the size of his own head after transformation.

Male. Transformation: 'Kiji Brother'. The only one without an alias. Age: 34. His personality is average, and compared to a 'plagiarism author' or a 'narcissist deliveryman', he is a very ordinary office worker. Well, he did get fired... later, he works part-time at Cafe Duri-Dungsil with Ga-bi. Before transforming, he is the shortest after Ga-bi and Purple Shark, but when transformed, he stands 2.2m tall. In his transformed state, he has wings on his back and can fly. He uses polite speech with the other members, except for Purple Shark. Weapon: Donblaster, though he rarely uses it.

Male. Transformation: 'Don Doragoku' (Normal Do-won), 'Don Torabolt' (Dark Do-won). Alias: Dual Personality. Age: 21. As his alias suggests, he has two personalities: Normal Do-won and 'Dark Do-won'. Normal Do-won uses polite speech with all members and is gentle, diligent, and kind. Dark Do-won has a violent voice, uses rough language, and wears an additional tiger-patterned robe. His posture is a crouch, and the red patterns of Doragoku turn white for Torabolt. Sometimes the two personalities split and act simultaneously. Exclusive weapons are the Don Axcpear and the transformation device Tigerguard.

Gender unknown, age unknown. Likely older than Ga-bi, but the Donbrothers members treat Purple Shark like the youngest. The sword 'Ninjark Sword' is the true form, and the physical body is an avatar manifested so the sword can wield itself. Touching it in sword form used to cause a rampage, but lately, it just manifests the body without the frenzy. During Avataro Change, the gear disk on the Ninjark Sword is played like a guitar. There is a certain gap-moe and cuteness to the character. The second manager of Cafe Duri-Dungsil.