Daum basically gives three translations:
- “a creature; a guy; a chap; a fellow; a bloke”
- brat – Good when used about kids or at least people who are younger than the speaker.
- punk – Vague enough to cover most of the meanings of 자식. It can range from showing that you’re a little bit annoyed to, “Do you feel lucky? Well, do ya, punk?”
- jerk – I like to use this when people are gossiping about someone they don’t like.
- bastard – If they’re talking about a guy who killed their entire family they shouldn’t just call him a “jerk”.
- guy – Use this when it’s not meant as an insult.