Pedo Paradise/Young/Park

It's a sunny afternoon and the older kids are in school, so it's mostly babies and toddlers playing or being pushed in strollers.

Your newspaper does double duty. It gives you a reason to sit on a shaded bench and covers your reaction to the tempting little morsels that parade past you. Some of them are wearing very little as whoever is supervising them believes that exposure to fresh air and moderate sunshine is good for them. One little girl, wearing only shorts and sandals obviously has an itch, because she stops nearby and puts her hand up the leg of her shorts to give her pussy a good scratch. The woman with her scolds her and then smiles apologetically to you as if to say; "What can you do?"

You are still thinking about that when a middle-aged man walks towards you pushing a child in a stroller. As they come closer, you notice that it's a girl with long, brown hair, tied back in a loose plait, She is noticeably fat. Not "a little overweight", or "well built", but pretty fat. The man pushing her is fat too and sweating. He comes to a stop and, after asking if it's free, sits on the bench beside you. "Hot, isn't it," he says.

You spend a few minutes discussing the weather and then he lifts the child out of her stroller. he seems to be about three years old and sits happily on his knee, looking around and especially at you. "This is Lilly," the man says. She's my stepdaughter."

"Hello Lilly. My name is Arthur." (Not a name anyone who knows me would recognise).

"Hewwo mister," she says and holds out a pudgy little hand. When you shake it, it also proves to be sticky.

"Sorry about that," the man says. "She had an ice cream earlier and it gets everywhere. Lilly is wearing elasticated shorts and a loose top. There's an expanse of bare flesh between them, exposing her fat belly with a deeply sunk belly button. Her feet are bare. She looks at her sticky hand and plunges it down through the elastic into her shorts and sits there, obviously playing with her pussy. You make sure the newspaper is doing its job. "You shouldn't do that," he says.

"Mummy says I can," she says and shifts on his lap so she has easier access.

"Her mother believes that discouraging children from exploring their bodies will stunt their development," he says with a shrug. Clearly an argument he's lost.

"I agree," you say. "I know everyone thinks that teenagers are all at it like rabbits these days, but there are loads of people who never enjoy sex because they are too inhibited."

"You're probably right," he says. "It can be embarrassing at times though."

You smile. "Don't mind me." You look down at the toddler. "You keep playing with yourself Lilly. Maybe Daddy will help you out sometime."

He looks shocked. "I couldn't do that," he says, but you sense a lack of conviction in his protest.

"I'm a firm believer in sex education for children. The earlier the better. Think how much happier all these kids would be if they were naked," you say. As you speak, an uptight-looking woman walks past with a little boy in long trousers and a white shirt. "Look at that poor kid. I bet he grows up to be a misogynist or something."

The man laughs. "You are probably right," he says. Meanwhile, Lilly has pushed the front of her shorts down to display her tummy and is obviously pushing a finger or two into her cunny. He looks down and sighs. "Do you want Daddy to help," he asks.

You realise that you totally misjudged the situation. "It's a bit public here," you say. You nod towards the public toilets. "Why don't we go over there." The toilet block is new and has a combination baby changing and disabled toilets in the gents as well as the ladies. You have the special key that's needed to get in.

It takes him a minute to make up his mind, but eventually, he puts Lilly back in the stroller. "I need a pee anyway," he says as you walk with them. The accessible unit is right by the entrance before it splits right and left for ladies and gents. You have the special key ready and follow Lilly and her father in, before locking the door from the inside.

The room is reasonably large and fully equipped. There's a WC, screened off in one corner with various supports to help the less able. On one side there's a table, set up for changing adults and another has a more normal baby changing table. "Lift her up while I pee," the man says. You do as he asks, marvelling at the weight of her. She's only a little over three feet tall but weighs as much as a kid twice her age.

She lays back on the table and kicks her legs in the air. You can still hear her father pissing into the bowl, so you pull her shorts and panties down to expose her chubby little pussy. She giggles happily and promptly starts rubbing it. "Such a little slut she is," her father says, coming up behind you. "I'm not her real father," he says. "She was still in nappies when I married her mother and it was a bit of a shock to find myself sharing the marital bed with a baby."

"Didn't that - err - cramp your style, having a baby in the bed?"

He shrugs. "At first, but her Mum didn't seem to mind and we just carried on, even when she was awake." He looks down at the naked baby and then at the bulge in your trousers. "You can fuck her if you want, she loves it," he says, pulling his own dick out.

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