Kill Bok Soon

A teen in both is being raised by a killer/group of killers. It affects their relationship. In Kill Bok Soon a teen doesn't know about them being a killer, In Hwayi: A monster Boy a teen knows and is being raised to be a killer too.

Working woman single mom trying to save her son fight against crazy evil villain. Intense, danger, one against group.

Assassin's/killer theme, both action packed would recommend if you've watched either or.

both have badass female leads with an ulterior motives and a backstory behind their doings. jiwoo was revenge driven in my name who wanted to avenge her fathers death. after a series of events she gets to know that the person she joined hands with is the real killer and that aggravates her thirst of killing. i feel like the protagonist of this drama also has a similar story.

Both movies have a FL with a "particular set of skills" that make them dangerous & useful.............................................

Both are a kmovie about a female killer, the two worked in a violent job and ended up killing everybody. Kill BokSoon has a more complex storyline with other characters, while ballerina has an emotional thing on it.