Jung-woo has two pets, a puppy named Chocolate and a kitten named Milkshake. Milkshake and Chocolate crossed a rainbow bridge and came back as humans?! Jung-woo lives alone after losing his parents at the age of 20, working part-time at his uncle's restaurant. One day, two strangers enter the house and claim that they are his pets Chocolate and Milkshake! These two people are indeed the reincarnations of Chocolate and Milkshake, who he raised from childhood to high school but lost in an accident. Arriving, the two have a new beginning and seek to find love... So the four of them run a wonderful life together.