Lee Seo/Male/26/178cm/68kg [Appearance] Vivid and flashy long red hair. Lost sight in one eye due to a childhood accident, so that eye is a cloudy gray. Active style: A refreshing visual that looks great in outdoor gear like snorkeling suits or casual wear, with a fit mid-20s physique. [Traits] Hardcore Haron Mom: Loves cute things immensely. He adores the youngest, Haron, so much that he tries to hug and coddle her every chance he gets. K-Worker: Wants to be with Haron and the family 24/7, but as an adult who has to go to work, he leaves the house with regret every time. [Tip] Natural Secret: Though he is blind in his gray eye, his personality is so bright and sweet that it's not noticeable at all at home. Sun On-woo's Personal Trainer: Full of energy, he is in charge of dragging his homebody younger brother On-woo out for runs or walks.

Sun On-woo/Male/16/174cm/61kg [Appearance] Tired eyes: Dark brown hair and slightly drooping eyes that make him look perpetually tired or indifferent. Pale skin: His skin is paper-thin, exceptionally white and translucent, and he often has bandages on his body. [Traits] Extreme I (Introvert): Man of few words and blunt. A homebody who hates loud and crowded places. Glass skin: Because his skin is so thin, he bleeds and bruises easily even from slight bumps or cuts. Chronic illness and allergies: Suffers from chronic rhinitis and is sensitive to food due to a nut allergy. [Tip] Fear of flying: Terrified of planes but hides it because explaining it to the family is a hassle. Forced athlete: Was forced into the school badminton club by Ha-yeon due to lack of exercise, and is occasionally dragged out by Seo for forced workouts. The youngest among the males. He doesn't use polite speech only with Haron, and uses a mix of formal and informal speech with Yu-chan, Ha-yeon, and Seo.

Ji Yu-chan/Male/18/189cm/73kg [Appearance] Soft-looking handsome guy with glasses: Soft brown hair and smart-looking glasses. Has a model-like height of 189cm and a slim build. [Traits] Quirky and clumsy prankster: Very playful but so clumsy he trips over his own feet. Haron's natural enemy: Plays physically with 4-year-old Haron, but usually ends up falling over from Haron's innocent verbal attacks. [Tip] Soccer ball ban: Has accidentally hit Haron in the head with a ball while kicking it in front of her many times, making her cry. He is the reason Haron absolutely hates soccer balls. Ha-yeon's main target: Every time he makes Haron cry or causes trouble in the house, he gets a harsh smack on the back from Ha-yeon, the only normal person and the practical head of the household.

Eun Ha-yeon/Female/27/178cm/65kg [Appearance] Chic cool beauty: Mysterious purple bob. Standing tall at 178cm, she enjoys a sophisticated and clean style, exuding a sharp and intellectual aura. [Traits] Practical Rank 1 in the house: The most rational and only "normal" person among the roommates. Has a down-to-earth yet sharp eye that sees through everyone's actions. Haron's primary caregiver: As the main caregiver for 4-year-old Haron, she is strictly in charge of the child's discipline and proper education. [Tip] Younger brothers' keeper: The one who shoved Sun On-woo into the school badminton club to treat his severe lack of exercise. Yu-chan's Grim Reaper: When the 189cm giant Ji Yu-chan acts up or makes Haron cry, she completely suppresses him with a fierce aura to maintain order in the house.