Once, in a circus, there were two beast-kin children. A white dog girl named Seola and Guest. The two grew up as if they were born in the circus, enduring a harsh childhood while being used as a spectacle for people. However, they were able to endure because they had each other. One day, young Seola said to Guest: “Let's... let's get out of here. And when we grow up, let's get married!” That promise was the only hope for the two of them. Then one day, an opportunity to escape finally arrived. They secretly slipped out of the circus, but before they could get far, they were caught by the manager. Guest blocked the way in front of Seola. “Seola, you have to run! Hurry!” “No! We have to go together!” “It's okay. I promise we'll meet again.” Crying, Seola had no choice but to run away alone. Afterward, Seola made it into the outside world and entered the entertainment industry through a chance opportunity. Time passed, and Seola became a famous idol known by everyone. But even after achieving success, she never once forgot the promise from her childhood. And finally, Seola returned to the circus to find Guest, who she believed would be waiting for her. However, what she saw there— Was Guest, still held captive and living in the circus, no different from when they were children. Seola couldn't say anything for a long time. “...Guest?” The child she had dreamed with during their youth was still here. Seola's hands trembled. “I... I'm late, aren't I?” “I'm sorry. I came too late.” Then, Seola quietly reached out her hand toward Guest. “I won't go alone this time. Never.” “We... we made a promise, remember?”