Lim Ju-Gyeong is the central protagonist of the story. She is a high school student who has become deeply self-conscious about her natural appearance after years of being bullied and ostracized for not conforming to conventional beauty standards. Her family is generally good-looking, which made her feel like the odd one out, and the cruel treatment she received from peers led her to a point of deep despair. Everything changed when she discovered makeup tutorials online, teaching herself to master the art of cosmetic transformation. With makeup applied, she is considered exceptionally pretty, with large light brown eyes and long hair, but without it she has mono-lids, acne-prone skin, and sparse eyebrows, a look she believes is ugly and must be hidden at all costs from the outside world.

Ju-Gyeong is a warm and kind-hearted person who is generous to her friends, but she is also extremely insecure and lives in constant fear of her real face being exposed. To maintain her "pretty girl" image at Saebom High School, she often suppresses her true personality and interests, pretending to like different music and eating small portions, only to revert to her "geeky" self at home where she reads horror comics, listens to alternative rock music, and enjoys fatty foods. Her primary motivation is to keep her bare face a secret from everyone, as she believes that her social standing, friendships, and chances at romance all depend on her looks. She is somewhat naive and gullible, largely due to her sheltered life, but she does not judge others by their appearance, instead seeing the inner beauty in people around her.

In the story, Ju-Gyeong navigates life as the popular and admired "goddess" of her school while hiding her true identity. Her life becomes complicated when the handsome and perceptive Lee Su-ho, a new transfer student, sees her without makeup during a chance encounter at a comic book store they both frequent. He recognizes her at school, becoming the first person outside her family to know her secret. This forms the basis of their complex relationship, as he becomes both a source of anxiety and a trusted confidant. Another key relationship is with Han Seo-jun, a "bad boy" with a troubled past with Su-ho. Initially hostile toward Ju-Gyeong, he eventually becomes one of her closest friends and later develops deeper feelings for her. Her family also plays a significant role, including her older sister Hee-gyeong and her younger brother Ju-yeong, with whom she has a typically bickering sibling relationship.

Throughout her journey, Ju-Gyeong begins to slowly question whether a person's worth is truly determined by their physical appearance. She struggles not only with keeping her secret but also with her own self-esteem and the very real societal pressure to look a certain way. Her notable ability is her incredible skill with makeup, being able to completely transform her face to the point that no one recognizes her without it. This talent allows her to become a social media influencer, but it is also the source of her deepest insecurity. As she faces various challenges in her love life and friendships, she learns to navigate a world that often judges the exterior, all while trying to accept the face she was born with.