This is sooooo money! I've field-tested this with great results!
After winning the 5 questions game (...of course! oh, and if you've never heard of the 5Q's game, research it! it's an awesome routine!), you tell her "with this game, you will NEVER have to buy another drink again! i guess i'll be nice and teach it to you, as a consolation for your loss."
after teaching it to her, you are faced with two fabulous scenerios:
1. you can use it to your advantage when a chump (or ANY Interrupt) comes up to the two of you. you simply tell the Interrupt "hey, check this out; she's going to tell ask you 5 questions, and you have to answer with 5 lies. If you succeed, she'll buy you a drink, but if you're honest in any answer, you have to buy her a drink" then you allow them to play the game. When she wins, he's going to look like a huge flopping idiot and she'll think you're fantastic for getting her a free drink (that you DIDN'T buy!). The chump will lose instant value in her eyes. If it's one of her friends that Interrupts, whether female OR male, you'll have increased value in your target's eyes and you can just befriend the Interrupt since you've shown that you're already rolling with the target, just laugh it off and have a good time with it!
2. if you're confident that there won't be anybody interrupting the both of you (a cocktail waitress included, as i'm sure she could play along!), then you can call in another guy and continue the routine where your target plays the game with him. Then after he loses (both the game and her value of him) you can tell him "well, thanks for playing! she appreciates free drinks!" and then move your target elsewhere.
Try this out and have fun with it!