Meet Aroon Duangporn, a young man from a wealthy family in Bangkok. He has a unique bond with his stepsibling, Dae, affectionately known as the little sweetheart. Initially, Aroon and Dae shared a deep affection for one another. However, a unfortunate event led Aroon to harbor a profound resentment towards Dae. This animosity intensified whenever Dae's charm grew, capturing the attention of others, including Aroon's friends and even his girlfriend, causing Aroon to view Dae as a deceptive devil, masquerading as an angel - a belief he firmly held onto. But what if the truth were different? What would happen when Aroon finally uncovers Dae's innocence? Could their once-hateful relationship between stepbrothers evolve into something more profound? As the story unfolds, we witness the complexities of their emotions and the possibility of change.