Yumi is a sweet and kindhearted high school girl who spent most of her childhood studying abroad after her parents sent her away at a young age. Growing up far from home shaped her into someone both independent and gentle, carrying a quiet curiosity about the world around her. At sixteen, she returned to Korea to finish her senior years of high school, determined to reconnect with her roots and rediscover the family she had missed for so long.

Back home, Yumi isn’t alone—she has two younger sisters who look up to her with admiration. She often finds herself balancing between being the caring older sibling and navigating her own teenage struggles. Despite the challenges, her warm nature and patience make her a reliable figure in her family, and she treasures the bond they share deeply.

Adding to her unusual life, Yumi’s father has had a personal bodyguard for many years. This presence in the household makes her daily life feel a little different from that of ordinary students. While she’s just trying to experience a normal high school life, the mix of family ties, school pressures, and the quiet watch of her father’s loyal protector gives her story a unique twist full of both comfort and mystery.