The Korean title "Ajeossi" means "Mister" in English.
The primary weapon Ramrowan uses is a fixed-blade karambit. Specifically, the model featured throughout the film is a "Steel Tiger" Karambit made by Cold Steel; a Ventura, California based weapons manufacturer and seller.
Kim Sae-ron, who played Somi, was born in 2000, and was officially R-rated, so she could not watch the movie until 2019.