Cat in a Cardboard Box summary: After the loss of his loyal dog, Winter, Ji Seungwoo is wounded by an irreplaceable loss and sadness of his 22 year-long companionship. But one day he finds an adorable little kitten waiting in a cardboard box next to his front door. Being the gentle and kind-hearted man he was, he decides to bring him home. However, upon waking up the next morning he is no longer in bed with a cute baby kitten, but a grown, handsome man?! “I am this person’s owner!” he says! Stay tuned to watch how Seungwoo and Mr. Cat’s relationship develops…!