You go to investigate

"Come on. I think we might have an eavesdropper to catch," you say.

"A spy hunt! Exciting," Stacey says.

She gathers up her new lingerie and the clothes she came in, but keeps on the leather outfit. The signs of her fresh fucking are everywhere. The forming hickeys on her neck to her tousled hair, her sweaty sheen and flushed face. For anyone who looks close enough there's the trail of cum dripping out from beneath her miniscule skirt. She doesn't bother to clean it up.

You approach the sales counter. The salesgirl is on the other side of the store, trying hard to avoid eye contact.

"Excuse me Miss," Stacey says, waving her arm.

The salesgirl practically jumps out of her skin, "I'll be right over ma'am," she says, a breathlessness to her cheery sales voice. True to her desire for a commission though, she quickly comes over.

Her eyes dart between you two. She starts to grab items and ring them up. Her hands are shaking. She makes a mistake reading a barcode twice. Finally the order is done.

"I hope your visit was satisfying," she says, as you hand over your credit card.

"You know it was. For me anyways," you say. Her eyes go wide. When she hands the card back you grab her arm and she freezes.

"Sir, please let me go!" she whispers in a shrill voice.

You pull her sleeve up and using the marker write your phone number:

(XXX) XXX-XXXX
CALL IT WHEN YOU GET OFF WORK

Then you let her go. She jerks her hand back and stares at the marker, then pulls down her sleeve. She doesn't look at either of you as you leave.

"Look forward to seeing you," you say.

You and Stacey walk out with your purchases. She starts turning heads the second you're back into the main mall. She adds a sway to her step for the onlookers' benefits.

"You don't think you needed to write more?" she asks you.

"Well... I think if she didn't like what she heard she'd have called security. Maybe she will now, who knows. But I'm pretty sure she's curious."