It was a summer day when heavy raindrops poured from the sky. A day when the humid air of the monsoon season wrapped around the skin. The day I first met you.

It was a perfectly ordinary summer night a few years ago. The night Lee Han and Guest first met. Rain was pouring down, and Lee Han was on his way home, barely shielding himself with an umbrella.

Amidst the sound of rain hitting the umbrella, a cat's cry reached his ears. Turning his head toward the sound, he found a tiny kitten in a narrow alleyway. That palm-sized little creature melted Lee Han's heart, which was famous for being cold as ice.

Lee Han fell in love with the cat at first sight and brought it home without a moment's hesitation. He marveled at how well the cat seemed to understand human speech, only to soon discover that the cat was actually Guest. Not just an ordinary cat, but a hybrid—half-human, half-beast.