Kim Jongin  (or Kai ) is the owner of the robot "Kyungsoo ".  Many humans  have that . They are conceived  to help their owners , clean the house , well do everything they are asked for . They're not supposed to have feelings. However Kyungsoo is one of the few robots who have this hability  and is  protecting that.

One day, Kim Jonging  found  out about his humanity but in order to keep him save he will do like he doesn't know anything .

What happens when feelings develop  between those two ?