What do you think about me going out with a girl in a non committed way?
Why do you want to go out with her?
I just wanted to have some fun
It is normal to date and get to know people and not be serious about them, but it is only okay if both people are okay with it. Leading her on is wrong and will hurt her feelings.
What? I didn't mean to lead her on, I said I'm not serious about her.
It's okay not to be serious, I'm only saying that it would be honest if you told her you're not serious because she might be serious. You don't want any confusion about what you both want.