You catch her shoplifting and corner her.

Following Becky around and watching her is pleasant enough, especially when she goes into a lingerie shop. Sadly she doesn't seem to want to try anything on or you'd try to get some candid photos with your phone, but when she leaves she hangs around the exit until nobody is looking her way (nobody but you, but you know how to keep yourself out of sight), and she sneaks her purse outside the detector.

She quickly walks away towards a dark corner near the rest rooms, and when she's sure she's alone (hah!) she digs up a rather risqué white lace bra and starts tugging at the price tag.

"Hello there, Becky."

"What? Who's there?!"

You step out where she can see you, and her face turns from fear to contempt.

"Oh, it's you. Run along, creep."

"I don't think so, Becky."

You waggle your phone.

"I saw what you did, and I've got the pictures to prove it. Oh, and before you try anything stupid, I've already sent them to two different mail accounts."