He wants to diaper her

"First, I would like to ask you to lay down on your desk."

Rebecca was confused, but she did as he told her to, laying flat on her back.

Out of the corner of her eye, she saw David take something else out of his backpack. It was pure white, and it crinkled noisily whenever it moved.

She quickly realized what it was.

"Is that a diaper?"

"What do you think?" David said with a chuckle, as he began to unfold it.

Rebecca was at an absolute loss, but before she even realized what was happening, David had flipped up her skirt, removed her panties, and taped her up into the bulky, thick diaper. He patted the front afterwards, saying "Now, isn't that better?"