So what is your girlfriend like?
What is she like? She sure exsists, that is for sure.
Yeah, right.

Of all the discriptions for a girl you can give, telling someone that they are "real" is a sure way to make them think that they are not. Next time try the truth.

So what is your girlfriend like?
I am not sure, I havn't met her.
Wow, she sounds really cool!