Lexie squirmed, barely keeping herself from grabbing her crotch. But she couldn't get mad at him or she'd lose her chance. She also imagined that lifting up her skirt to examine the problem with her underwear would be bad form. (Little did she know it, but the skirt was short enough that only she was unable to see the padding beneath it. "Oh... good. Pizza..." Please answer my question now... gotta go gotta go gotta go...

Alastair took his time getting the pizza, pretending to have lost his wallet. Eventually he made it back and sat down. He noticed she still hadn't wet herself. An idea sparked in his head.
"Here you go." He said.
He grabbed a slice of pizza and leaned over to give it to her. As he did so his hand 'slipped' and went down on her bladder.

Lexie first assumed this was his attempt at being suave to get under her shirt. It was cute, and sexy.
Then she realized that he had accidentally... oh crap I really have to pee! She squirmed, making one last attempt tohold it in, but couldn't. Her bladder relaxed, muscles gave in.
And yet... she didn't feel much of it. She felt the urine stream out abd a warmth pooling at her crotch, but nothing else. No trickle down her leg or spilling onto her skirt, just a warm absorbant pooling.
Oh god I hope he doesn't notice, she thought as the designs on the front of the diaper faded and were replaced by a yellow stain.

Alastair knew the job had been done. The room was dead quiet for a second. Then the hissing noise started.
Alastair turned to Lexie. "Did you just pee yourself?" He asked.
He didn't wait for a response and looked under the girls skirt.
"And in a diaper aswell." He said putting on a fake look of surprise. "If I didn't know better I'd think you were a baby."

Lexie turned bright red, looking down to see her new undergarments. "But... I... That's not mine!" She protested weakly, her cheeks the color of ripe tomatoes she was blushing so hard. So that's what the feeling was... but how? "I don't wear diapers!" It sounded like an obvious lie, due to her exasperation ajd of course the soggy, nearly leaking diaper around her waist.

"I'm sure that's true." Alastair said mockingly. He was loving this moment. His dream of babying a girl was about to come true.
"Let's go and get you changed." He sighed, picking the girl up and cradling her once again.
He walked over to the spare bedroom and layed her down on the change table.

Lexie was confused. What? He's taking this all in stride... surprisingly so. Change? "I don't need a diaper change, I don't need diapers!" She protested. "I need clean panties..." oh god. Why did I bother saying clean? "Really! I don't have accidents in my panties ever!" Not good. Why am I saying this? "And I never EVER have a poop accident, eventthough I'm lactose intolerant..." Shut up, me!

(The Lactose Intolerant girl wanted Pizza? :) )

Alastair had already begun changing her. He took off her skirt.
"You wont be wearing this any more." He said.
He then grabbed a baby wipe and began wiping her private regions.
"If you don't have accidents, what do you call what you had before?" He asked.

(She has those pills that let you eat dairy. Forgo those, however, and dairy equals extreme gastrointestinal distress and the need for clean panties or else a day on the toilet.)
"I... It was a one time thing. It never happens! Besides this once..." she was blushing even more now, but didn't fight him, raising her legs to be changed like she knew the drill. (Two siblings ages one and three meant she did know the drill.) "I swear I don't need diapers. Really! Uh, don't forget to use plenty of powder," she pointed out. Oh dammit, why do I keep talking...

Alastair nodded and powdered her private region. He slid the diaper under he waiting legs and did it up at the front.
He then pulled out a pair of mittens and put them on her.
"We wouldn't want you taking off your diapee now would we." He cooed.