Unrequited love is like breathing in fine dust: toxic, yet impossible to avoid. For over five years, Dahye Jung has harbored a relentless crush on her childhood best friend, Beomseok Lee. She vows to make one final, undeniable confession the moment her college entrance exams end. But her grand romantic dream is shattered when she catches him having a secret kiss… with her own older sister! Caught in a messy web of betrayal, petty resentment, and a chaotic four-way romance, Dahye’s lifelong crush is about to become a total disaster. After all, love hurts, but family hurts worse.