Lol good idea but wont it seem obvious what your upto if you pull out your mobile too and walk right next to her? you just know theres people watching (especially at the mall!). I can just about overcome my AA but If I know theres alot of people watching then uh..I get pretty scared

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And my main concern is whatever you say witty or otherwise she would be too distracted to hear. Even if she heard me say 'I'm waiting for the girl to get off her phone so I can talk to her) she might find me funny or just wonder what the heck I'm on about, but most likly she isnt going to stop talking to her mobile midway, Which still doesn't solve how I would open or what kind of excuse can I use to lurk around and wait for her to finish without looking like a stalker?