Chapter 1 - Stacey discovers anal

Stacey is sitting at the end of the dinner table. She's deep in thought, thinking about something she overheard from a girl at school earlier that day. Sitting by herself in the school cantina as she often did, she overheard a group of girls walking past. «…It is SO amazing! Luke’s cock is so long and thick, and the sensation of having him in my ass is just mind-blowing!..». She had always thought of it as scary, and even though some guys had wanted her ass before, she could never do it – fearing it’d hurt. Instead, she had focused on getting as good as possible at blow jobs. Chris had told her that mom was awesome at them, and Stacey wanted to be just as good, to be able to please dad.

The family dinner is a sacred thing for the McKay family, and they are all gathered around the large dinner table in the kitchen. Her mom Hannah and her dad Tom sits on their regular seats on either side of her. Across the table Chris is sitting in his soccer jersey, shoveling down the food like there is no tomorrow. Stacey doesn't have much of an appetite.
"Mom?" she asks.
"Yeah, hun?". Hannah looks at her daughter, recognizing the sort of coy tone in her voice, indicating that she's thought of the upcoming question for a little while.
"When did you first try anal?"
"Uhm, that must be.. when I was 19 I think? I had just started seeing this guy from school, and he was completely obsessed with my ass. Had a huge dick unfortunately, and no patience to get me used to him. Not my most pleasant sexual experience."
Stacey looks at her, wide eyed and bleak.
"Oh, sorry honey, I didn't mean to scare you! When I got used to it, it was wonderful. It's something quite different from having your pussy fucked."
"..oh, ok. Well, I've been sort of curious to try it. I've fingered my ass a bit, and I really like the feeling.
Chris looks up from his plate, grinning widely. "I'll happily fuck your ass little sis!"
"No, you'll be just like mom's boyfriend, making it hurt!"
Hanna smiles. "You know what" she says. "I have something to help you get warmed up". She walks to the bathroom as she yells back to the kitchen. «I often used this when Iwas younger, but now that I'm used to your dad and Chris, it's a bit too small for me. You can have it".

She comes back holding a small buttplug in one hand and a tube of lube in the other.
"Come here" she says as she lubes up the plug. "Lift up your skirt".
Stacey looks at the buttplug with excitement gets up from the table.
"Bend over"
Bending over the kitchen counter with her ass facing the whole family, she lifts up her skirt and does a cute little dance, jiggling her plump buttocks.
"It's not usually you who gives me that order" she laughs, as Chris blushes a bit.
"Spread 'em for me" Hanna says, and starts massaging some lube into the cute little anus as Stacey spreads her ass cheeks wide. Then she puts the tip of the butt plug against her asshole.
Stacey jumps slightly from the sudden feeling, producing a little laugh from her father and brother, who have both stopped eating to watch the show.
"Ok, now with anal sex, it's very important that you relax. You have two muscles down there, and one of them you can control quite freely. The other one is a bit harder. Just take a few long breaths and try to relax.
Stacey closes her eyes, and tries to relax her sphincter. With a slow, but steady movement, Hannah shoves the butt plug all the way in, so that only the small, flared base is visible.
"There, how does it feel?" she says, as she walks over to the kitchen sink to wash of the lube.
"A little strange. I kinda feel like I need to poop, but it also feels good". 
"That's good, I bet you'll start to love it pretty soon. In fact, all this talk of anal sex really got me worked up. I might need some help with that after dinner guys" she winks to Chris.
As she sits down, Stacey can feel the base of the butt plug hitting the seat, and pressing it even further up her ass.
"You should wear it to school tomorrow", Hannah says. "To get used to the feeling".
Stacey felt herself getting horny by the thought of walking around school with this thing constantly arousing her.