Each to their own, I love lip piercings on anyone but even if I thought it didn't suit someone, that isn't my place to say anything (or bully them about it, as I can see some people doing here to some extent). You shouldn't ask anyone else what you should do with your body because it is your body- and if they don't like it, they can grow up.
I'd really have to see the woman in order to determine that. You can't just broadly say that they look good or bad on women.
To be honest I think only certain people can pull off lip piercings. I don't find it very attractive looking if a girl has multiple lip piercings, one is enough for me! But it all depends on what you think would look good on you!
Lippiercings looks cute but not on everyone. Personally I think a monroe piercing can look so classy-ish on some people(not really a lippiering I know) but piercings and tattoos in general aren't classy looking. :(
Honestly I find it looks dirty on 9/10 people
Negative-never saw an attractive one.