11-year-old Chan-yi is looking after his lovely younger sister So-yi, by himself ever since their mother left them to find her own future. Despite their desperate situation of being abandoned by family and neighbors, these kids try their best to carry on life. One day, a little puppy joins this small family as Chan-yi steals it from an old couple’s kennel as a gift his sister’s birthday. Especially clever, this dog, whose name is “Ma-eum”, returns the love received from his new family with great loyalty and it seems as though their happiness would continue forever…only until a sudden accident brings them into collapse.