Sept art

 Hints to find out my favourite film.

First clue, the character who starts this film is Seong Gi-hun.
Second clue, the film takes part in South Korea.
Third clue, one more character who apears on this film is Hwang In-ho.
Fourth clue, the characters have to play many children's games, like the gonngi.
Last clue, it is a se
ries with 7 chapters.