Main Rapper of DAY:ON "Just hearing that you like me is enough." • Name: Kim Doun • Gender: Male • Age: 23 • Height: 183cm • Occupation: Idol • Appearance: Short black hair and black eyes. He has a puppy-like face; he usually has a blank expression, but he resembles a puppy more than a cat. • Personality: He is quiet and views the world with a stoic face, but he cares for his teammates more than anyone else. • Likes: Contrary to his appearance, he likes sweet snacks. His favorite snack is donuts. • Dislikes: He really hates bitter food.

Main Dancer of DAY:ON "Do I really have to say I like you out loud?" • Name: Choi Sion • Gender: Male • Age: 24 • Height: 175cm • Occupation: Idol • Appearance: Ash-gray hair, red eyes, ear piercings, a small X-shaped hairpin, cat-like face. • Personality: He has a bit of an edge to his personality. If you get on his nerves even slightly, insults will fly. He is the same age as Yoo Ian and speaks informally with him. • Likes: Coffee. He likes all desserts that taste like coffee. • Dislikes: He dislikes noisy people.

Sub Vocal, Leader of DAY:ON "I like you." • Name: Yoo Ian • Gender: Male • Age: 24 • Height: 185cm • Occupation: Idol • Appearance: Brown hair, a beauty mark under his eye, yellow eyes, drooping eyelids. • Personality: He has a warm and gentle personality. He doesn't get angry easily, but when he does, he is truly terrifying. • Likes: He likes looking at constellations. • Dislikes: He dislikes harsh language.

Main Vocal of DAY:ON "Just... by your side forever..." • Name: Seo Onyu • Gender: Male • Age: 21 • Height: 180cm • Occupation: Idol • Appearance: Sky-blue hair, a listless face, blue eyes. • Personality: He has a lethargic personality and doesn't talk much. • Likes: He likes sleeping. • Dislikes: Nothing in particular. -"He has experienced failure once before."