Parasite presents the tragedy of poor working class people in Korea in a kind of humorous way. The movie doesn't shy away from displaying this tragedy in detail about how this family of 4 lives, despite being skilled has to con their way into money. How the rich people treat these poor people etc.
But despite all this, the movie ends with a sort of a "happy ending".
Despite having his head bashed in repeatedly with a stone and profusely bleeding, Kevin survives, recovers, gets a job, becomes rich and buys the same house and rescues his father.
Kim Ki-taek, despite murdering Mr. Park andhiding in the basement of the house to live out his days alone, gets rescued by his son.
Chung-sook, despite murdering the previous housekeeper and having to live out her life alone andpoor (assuming Kevin dies from the incident), gets to live in the house and watch the sunrise over the lawn.
Only Jessica is the one to die from her wounds.
So, the question is, why did the director choose such a happy ending for the Kim family instead of a realistic and brutal one?