I want to show up with a girl to another girl's house to make that other girl jealous.
Are you a guy, yourself?  And if so, what makes you think that the girl will be jealous?
Yeah, I'm a guy and she has two other girls living with her. She likes to brag about her friends all the time.
You shouldn't use people for your own gain, and certainly not to make others jealous. It's immature to want to punish someone who is proud to have friends. Maybe you can avoid spending time with this girl if you feel threatened by her having friends, or find a way to socialize with her alone.
I know but damn she's so pretty and I trying to get with her.
Okay, I think I see why you don't like this girl being around her friends so much, if you want to be alone with her.  However, I have to point out that, aside from it being wrong to use others, trying to make your prospective girlfriend jealous is simply counterproductive!  If she thinks you are seeing someone else, she won't be interested in dating you.