She says nothing, so the twins take charge

Mackenzie remained silent. She could feel her pale face turning redder and redder by the minute, while her eyes, wide in embarrassment, kept moving from one twin to the other. She barely noticed when Nicky nodded to Lily, who then nudged her lightly with her arm. "Come on in." She followed inside the store, walking unsteady on the narrow aisle between the shelves, with Nicky right behind them.

"As you see, we cater to all kinds of tastes." Lily's voice rang softly in Mackenzie's ear. "Something to scratch every itch. What's yours?" The redhead suddenly felt Lily's hand cupping her bare ass under the skirt.

"Whh...." The blurt that escaped Mackenzie's lips was intended to be a question, but she never got to finish it. Lily's hand moved up, lifting her skirt up and baring her ass. "Oh, look at that." Nicky sounded surprised and amused, looking down at the spank marks and the belt. "You've been a naughty, naughty girl, Mackenzie. Did you know that?" Mackenzie remained silent, immobile - only her full breasts lifting and dropping with her quickening breath, while the two siblings admired her derriere.

The silence lingered for a few more moments, and it was Lily's turn to nudge the customer. "Tell me ... " Lily whispered as she cupped the redhead's generous ass with both her hands. "Who did this to you?" Mackenzie felt the warm and wet touch of Lily's tongue spreading her cheeks and teasing her rim. The belt had stopped its buzzing for a few good minutes, but she could distinctly feel her clit and labia achingly vibrate. The unmistakable sensation of arousal radiated from her anus across her entire pelvis, as Lily's tongue pressed against her rear entry, opening it and pressing in.

Mackenzie's intent was to reach back and push Lily away, but once she touched the woman's blue hair, she pushed her face harder against her ass. "Deeper..." She whined with her eyes closed, leaning with her elbows against the counter. Lily's tongue, unnaturally long, twisted and turned reaching deeply inside her. Nicky's spank on her ass felt like a jolt.

"Please...." Mackenzie begged. "Let me ... Let me cum... " Already worn out by the belt, and driven mad by Lily's tongue, the redhead could barely gather a coherent thought. The memories of Saturday came back vividly, finding herself in a similar situation after less than two days. Lily was not in a hurry to oblige her, and Nicky took charge, in his casual tone. "Not if you won't tell us everything".