Cause I think this girl did it on purpose. I asked her to get something for me and she walked over to it, lined herself perfectly and bent down in an L shape to pick it up. Naturally I checked her out the entire time, even after she got up and turned around. I looked at her face afterward and she was smiling. Does that sound like it was on purpose and do girls like you looking at them if they're shoving their ass in your face
Ask her about it. She may have done it on purpose and she might not have. Some girls can't help it and they're just naturally sexy haha. Tell her that you couldn't help but notice her when she did it and try and build off of there, try not to sound too creepy just in case she didn't do it on purpose but try to hint at the fact that you found her quite beautiful (try to avoid sexy until you know she did it on purpose).