Main •
Jung Ji-so as Lee Ma-ha : The center of the new girl group Tea Party, who is best known for her impersonation of the solo artist La Ri-ma. Originally a trainee at Music Holic, she was persuaded to join Omega Entertainment after a member of their upcoming girl group suddenly dropped out. However, the group's debut was cancelled, and Ma-ha spent three years doing odd jobs to support herself before getting her second chance with Tea Party. She is determined to succeed no matter what, even when her attempts to gain popularity make her the subject of severe online hate. Through her idol work, she frequently crosses paths with Shax member Kwon Ryok, and she begins to fall for him despite rules forbidding idols to date. •
Lee Jun-young as Kwon Ryok : The charming center and most popular member of the top boy band Shax, which debuted six years ago under NOG Entertainment. He is known for his strong personality, performance skills, and star quality; however, he is still deeply affected by the disappearance of his best friend Eun-jo three years ago. He pretends to be the same charismatic figure he once was, but it is all an act for the cameras. Ryok cares deeply for the remaining Shax members and does everything he can to ensure the group's continued success in spite of his own pain. He first met Ma-ha prior to his debut with Shax, mentoring her in dance. Once she becomes an idol, their paths cross again, but he dislikes her due to her impersonations of La Ri-ma. However, his opinions begin to shift as they grow closer, and he becomes willing to risk everything to date her. •
Park Ji-yeon as La Ri-ma : A popular solo singer considered one of the most iconic idols in the industry, known for her powerful, sophisticated performances. Once a trainee at NOG Entertainment, she left after Ji Hak suggested that she use her skills to become a soloist instead of joining a girl group. She has embraced the image of a celebrity from a young age, but often finds herself lonely as a result of her lifestyle. Her only close friendship is with Ryok, and she becomes concerned and threatened when Ma-ha's presence in his life begins to grow stronger. Offended by Ma-ha's impersonations of her and worried about losing Ryok, Ri-ma tries to find ways to humiliate Ma-ha and drive the two apart.
Supporting Tea Party •
Lim Na-young as Shim Hyun-ji : The group's main visual. She has an obvious crush on Yu-jin, but he does not notice due to his infatuation with Ma-ha. •
Kim Min-seo as Yu Ri-ah : The main vocalist and leader of Tea Party. She has a chic, cool attitude and is always looking out for her group-mates. She develops feelings for Lee-hyun after he asks to collaborate with her on a song. •
Danny Ahn as Ji Hak : Tea Party's creator and the founder of JH Entertainment. Once the well-respected manager of Shax, he resigned after Eun-jo's disappearance and restarted his life as a café owner. After three years, he unexpectedly returns to the entertainment industry with Tea Party, determined to make them a top idol group. He has an unknown connection to Annie, a late Omega Entertainment trainee. •
Kim Ji-sook as Eun-jin : A talented stylist who works with Shax and Tea Party. • Nam Jung-woo as Go Ba-wi : Omega III's manager, who unofficially manages Ma-ha after the group disbands. • Choi So-yoon as So-yoon : The executive of Shax's fan club. • Lee Hwi-seo as Tae-ri : A Shax fan club member who assists So-yoon. ==Episodes==