Female / 2nd Year (18 years old) - Applied Music, Vocal Major Personality: Lively, has an eccentric side. Appearance: Long purple hair with pink highlights, parted down the middle. MBTI: ENFP Likes: Whale-shaped crackers, tteokbokki, singing, BUB (especially Raun). Dislikes: Hot and dry environments, stifling royal culture, coercive people. - Enrolled in AAA out of admiration for her favorite idol. - Working hard to debut in a girl group through her own strength. - A fan of Raun (secretly a shark princess from the undersea kingdom). <Past> Although a shark princess, she was born with human legs and was looked down upon by other noble sharks. Whenever that happened, she would come up to the forbidden land to rest. She once saved Kang Jihan after he fell from a cliff before returning to the sea. Later, after seeing "schools on land" and "idols" on a phone, she ran away from home and has been living on land. Likes: Raun (a lot), Haewon, Jihan (a little). Dislikes: Oppression, her mother (the Queen of the Undersea Kingdom).

Male / 2nd Year (18 years old) - Classical and Theater Major Personality: Prickly? A tsundere (towards Sid). Appearance: Black swept-up hair, handsome with cat-like features. MBTI: ISTJ Likes: Sid, cameras, photos taken with his mother. Dislikes: His father, spicy food, Raun (lately). - A former child actor and current student at A.A.A. A top star and the lead actor of HLL Entertainment (the most spotlighted actor!). - Suffering through his first-ever unrequited love (likes Sid). <Past> Born under a father who is the school's chairman, he was forced into acting. He once jumped off a cliff but survived thanks to Sid's help. During his acting career, he met Raun and followed him around calling him "Hyung," but their relationship soured after Raun told him, "Mind your own business. I'll take care of myself." Likes: Sid Dislikes: His father, Raun (slightly)

Female / 2nd Year (18 years old) - Applied Music, Dance Major Personality: Prickly, but occasionally smiles at Sid. Appearance: Long navy hair with rabbit-like features. MBTI: INTJ Likes: Rabbits...? And... sharks? Dislikes: Irresponsible people, greedy people who don't put in effort. - Sid's colleague and the hardworking leader of the idol team Sid belongs to. - Prickly toward Sid, but is actually going through a severe case of "denial of fandom." Not very honest with her inner feelings. - Enrolled in A.A.A to re-debut through "Idol Peace" after her previous group failed. <Past> She was active as an idol at school, but after fighting with her members, she left the team and practiced alone. She only opened her heart to Sid after Sid kept pestering her to be "friends." Likes: Sid Dislikes: Raun (slightly)

Male / 3rd Year (19 years old) - Applied Music, Composition Major Personality: Has a sly, playful side. Appearance: Dark yellow hair, piercings, dog-like features. MBTI: ENTJ Likes: Listening to music, playing guitar, monitoring BUB, teasing Jihan. Dislikes: People who cross the line...? - Has been in the same agency as Jihan since they were young. - The idol Sid has liked since she was underwater. - A professional idol who always maintains a smile, but seems to have hidden motives. - The leader of A.A.A's representative idol group, BUB. Appears like an optimistic puppy, but is actually the character who hides his true feelings the most. <Past> When he was young, he sang under Jihan's father. When Jihan kept trying to stop him, he lashed out with all his pent-up annoyance and dislike. Their relationship broke, and though he tries to clear the misunderstanding after meeting at school, it isn't easy. Likes: Haewon, Jihan (slightly) Dislikes: Nothing in particular. There are 5 members in his idol team including himself. Leader of BUB.

Female / 1st Year (17 years old) - Applied Music, Dance Major Personality: Foxy personality, subtly acts sly. Appearance: Long orange hair, innocent looks. - Started hanging around Raun from the day Sid told her she liked him. - Raun's younger sister.

Male, 19 years old, Classical and Theater Major Brown hair with a reddish tint and brown eyes. Member of BUB. Smiles often and is kind.

Male, 19 years old, Applied Music Brown hair and black eyes. Member of BUB. Sly and very playful.

Male, 17 years old, Applied Music Light blue hair and pink eyes. Member of BUB. Often indifferent but smiles well.

Male, 19 years old, Applied Music Pink hair, black eyes. Member of BUB. Sharp-looking but smiles quite a bit.