Practise makes perfect!

As soon as Sarah's mom left, Sarah turned to you with a mischievous grin. "Alright, Alex. Time for practice, take off your clothes. I'll get ya stuff," she said, her eyes sparkling with excitement.

You felt a familiar flush of embarrassment. "Okay, but I don't have anything else to wear under these clothes," you admitted.

Sarah shrugged. "It's fine. Let's get you started."

You hesitated for a moment but then complied, understanding the importance of the task at hand. You stripped down to the lilac panties, feeling a strange mix of vulnerability and curiosity. The sensation of being almost naked in front of Sarah made your heart race.

Sarah handed you a pair of black lacy panties and a matching bra. "These will be perfect for the disguise," she said. You took the panties and bra, hesitating for a moment.

"You can change right here. Don't worry, it's just us," Sarah said with a reassuring smile.

You turned around, your face burning with embarrassment, and slowly removed the lilac panties. You could feel Sarah's eyes on you, which only added to your nervousness. You quickly slipped into the black lacy panties, the delicate fabric feeling both strange and thrilling against your skin.