Stealing Mommy's Heart

Sienna sprinted across the rooftop and leaped into the air. With a squeeze of the controller in her palm she launched the grapnel lines from the canisters hanging from her belt, which dug into the stone wall of the next building across the street and pulled her flying forward.

She could only hope that nobody was looking up, given that her bare legs and high-waisted underpants were hardly suited to being stealthy in the dark.

She brought her knees to her black jacket and landed in a bare foot spin on the next rooftop, then risked a glance back up. The estate of Lady Dimitrescu loomed far away with its many windows gleaming up all six stories. The chill she felt wasn’t just from the cool air on her bare legs, or the embarrassing sensation of her elegant underwear being on full display.

There was a flash of motion, and Sienna huffed and spun away. She leapt across an alley, as something brushed by close enough to send her short shoulder cape fluttering in its wake.

The city was all downhill from Lady Dimitrescu’s mansion, and Sienna leapt from rooftop to rooftop, occasionally firing her gas grapnels to launch herself across wide streets, or making sudden unpredictable turns in midair.

Glancing over her shoulder, she saw it now. How the diaper managed to float like that was beyond her knowledge. With a sudden burst of speed it launched itself right at her, and Sienna ducked and barely managed to evade it with a quick firing of her grapnels.

She ran and jumped and ducked and weaved, and must have been halfway down the city when she made a jump and realized that there was no building opposite for her to latch onto.

With a hiss she spun about in the air, and fired her grapnels back at the bank which she’d just launched from. The coils pulled tight, and then she began swinging back down, until she hit the ground running and didn’t stop. Through the empty market square, thankfully nobody was out or about yet. The city’s greatest thief was known by reputation for her unique grapnelling, and right now anybody would make the connection with the woman running in only her underwear from the waist down. Hopefully she’d at least shaken the diaper.

She raced towards the looming buildings across the market and pushed her hips to get a good firing line, only for the grapnels to fizzle and fall limply to the ground. Dammit, out of gas. She’d been pushing them too hard in her frantic race.

She ditched the canisters in an alley. No use having the extra weight now. Hopefully they’d still be there in the morning when she came back for them.

Her sprint carried her through to another open square, and- Right into the grounds of the women’s clothing store owned by Lady Dimitrescue. Her eyes widened as she realized her mistake, and the impossible happened yet again.

--- Earlier that night --

Sienna walked the rooftops towards her destination. She conserved her gas for now, only making a few large crossings when the alternative was a long detour on a night when her path was all uphill.

Below her, the last carriages and even a few automobiles puttered their way home. It was a chilly night, and she crossed her arms beneath her short shoulder cloak. Progress was slow, and she began to worry that it would be near dawn by the time this job was done.

It was an age before she finally climbed the hill. The old tower beside Lady Dimitrescu’s estate would do nicely. She fired her grapnels and sailed up over the iron fence, then quickly retracted and fired them again to pull herself towards the manion’s roof. She was almost ready to get inside if only for the warmth. Of course, the rumoured treasures had an appeal too. Lady Dimitrescu’s Heart was legendary, and Sienna imagined that it had to be some great big jewel.

She picked out a dark window and swung herself in, and landed on the rafters of a large two-story room. Somehow she’d never considered that House Dimitrescu’s six stories might house only three double floors. Then again, she’d heard that Lady Dimitrescu was big, over nine feet if the rumours were to be believed. It was partially why she’d come here, just to see for herself, and this newest development seemed to match the impossible claim.

The entire estate was a mystery, even to her various underworld contacts who could deliver maps of most anywhere, and she only had the vaguest notes from some loose-lipped servants. Apparently there were gardens in the middle, big enough to house a swimming lake.

It would be easy enough to lower herself using the grapnels, though their reeling coils were loud enough to be heard in a quiet house interior. She walked the beams towards the narrow strip of light from the door below. Her eyes began to adjust and she made out several large crates below. No, wait, wooden cages? No, cribs.

She frowned and went still. Wait, was she in a nursery? Looking around she began to make out shapes. Doll houses. Rocking horses. A changing table, stacked high with diapers. Maybe even some tricycles? They would be a bit big wouldn’t they?

Her staring was interrupted as the door opened. Two women in nanny uniforms marched in, and the lights began to gently intensify.

Then there was an impossible sight. A woman entered through the door who loomed over the nannies. She wore a cream wrap dress and had a matching wide brim hat.

She could only be Lady Dimitrescu.

Her skin looked somewhat palid, almost otherworldly. Beneath rows of pearls, the neckline on her dress revealed some truly… titanic tatters. Sienna couldn’t help but stare, despite herself.

Then it dawned on her that she was two stories up, not one, and her sense of scale was off. The nannies… They were huge. And that meant Lady Dimitrescu was even bigger than she’d realized. Why, if she herself was standing beside her, Sienna might only be looking at the woman’s impossible rear end.

But that meant, the rocking horses, the doll house, the tricycles which had already seemed kind of big… Sienna glanced back to them, realizing that they were huge too. And the cribs...

She glanced at the cribs. Now that the lights were on she could see that there were figures in each of them. All girls. Each laying on her back in a footed sleeper with a telling bulge between her stomach and knees, a unique shade to each. Each sucking on a large pink pacifier.

And, as Sienna tried to get a sense of their scale, she realized that each was… Wait, was that Grace Van Camp? The snooty noble’s daughter who’d gone missing a few months back? And there, that looked like the last princess from two hundred years ago, whose painting the loyalists still hung everywhere. How in the world?

The nannies began lowering the edges of the cribs one by one, and easily scooped the ‘girls’ out. Each immediately ran to line up before the towering Lady Dimitrescu - if their awkward waddling could be called running - and looked impossible tiny before her.

The Lady of the house, for her part, looked very pleased with herself as she stood with her hands on her hips.

“Good morning girls,” she said in a deep, booming voice.

“Good morning Mommy,” they replied in unison.

Mommy?

“Now somebody in here has been naughty,” she said, clucking. “You know that Mommy doesn’t like you trying to keep your diaper dry all night.”

The ‘girls’ shifted nervously, and some of their hands drifted to rub their thickly diapered bottoms.

Then, Lady Dimitrescu’s head swivelled, and she stared directly at Sienna.

The thief gasped. In all her time being a legend in the city, being caught had never happened.

“Ah,” Lady Dimitrescu boomed. “I thought I felt some hungry eyes looking for some milk.”

Sienna was already turning about, almost slipping in a most uncharacteristic moment of nervousness, when the house began to move.

Or, not exactly, but instead things in the room began to move. A diaper floated up off the changing table. A nearby huge closet swung open, and a frilly dress raced out.

Sienna didn’t take any chances. She fired her grapnels straight at the window and anchored them on either side, then reeled them in to fire herself forward and out. Once outside, she spun about and fired another grapnel back up at the roof, needing to gain height to clear the fence.

She arced up over the roof, then brought her padded boots down on the tiles. Except… She sank into the tiles. They’d somehow come… alive, and were wrapping themselves around her feet.

With a gasp she kicked and leaped back, abandoning her shoes, and fell backwards from the roof. Ahead was the tower outside the Dimitrescu mansion, and she fired her grapnels at it in a corkscrew pattern, and twisted herself back upright as she pulled forward.

She was going to make it! She-

The fence reached up at her. She didn’t quite react in time, not quite sure what she was seeing, until the black, wrought iron fencing had grasped at her pants ankle.

“Come back here little girl!” a delighted voice boomed from the window.

The fence tugged, and Sienna began to go backwards. She pressed again to reel in her coils, but they weren’t made to pull somebody from an anchored position.

With a cry she released her hand controls and began fumbling with her pants. The living fence tugged, and down went her pants. She was left in only her underwear! The city’s greatest thief, and she’d just had her pants stolen!

She regrabbed the controls, and flew away from Lady Dimitrescu’s estate. She landed on top of the neighbouring tower, and took hold of the spire to look back at the impossible scene which she’d just escaped.

Then she saw the items flying after her, easily clearing the estate’s boundaries. A diaper, a dress, a pacifier, and more. Was that… a butt plug? Sienna had been questioning buying one of those, even stealing one, but either way it felt rather embarrassing.

And at the window was Lady Dimitrescu, grinning with huge pearly whites.

Sienna didn’t waste time. She turned and leapt away, and used her grapnels to pull herself down towards the next house. She changed course once she’d broken line of sight, guessing that Lady Dimitrescu’s magic only worked where she directed it. When creeping around the city Sienna had found some hints that magic was real, but she feared that she’d just stumbled into something far larger than her.

Down the hill she went, racing and zigzagging. Annoyingly, she soon realized that the diaper was still after her. She lowered herself beneath the rooftops, sailing under arches and down long tunnels with fast handiwork of her gas grapnels, only to look back and see that the diaper was still there. Dammit.

--- Twenty minutes later --

Sienna stumbled in front of Lady Dimitrescu’s store. Before her, mannequins in lingerie posed in the windows. Around her, huge, decorative iron fences curved about the courtyard.

The fences began to move.

No.

Sienna reached for her gas canisters, then remembered that she’d ditched them. No no no, she’d wasted too much gas with her antics.

She bolted for the open entrance between the fences. She almost made it too, when one of the iron bars bent and slipped between her panties at the hip. The sudden snag sent Sienna tumbling, and when she came up her panties were gone. She looked back in horror to see the fence lifting them away, well out of her reach.

Then the diaper hit Sienna’s crotch from the front.

She gasped as she fell to her back, then immediately rolled in a reflexive, expert dodge. Unfortunately, that just gave the diaper a chance to wrap up over her exposed bottom.

Sienna gasped as the diaper hoisted her up, actually lifting her from the ground, and then returned her to her feet. It was so bulky! She couldn’t even bring her knees together!

Her feet brushed hopelessly at the ground, but she couldn’t even budge the diaper from the position in the air.

Then, the diaper began making her walk back towards the big hill in the middle of the city. Though not exactly, it simply turned from one side to the other, giving her a dumb waddle while her bare legs moved helplessly, with her feet slapping the ground.

Sienna opened her mouth to cry for help, quite sure she’d rather be caught as a thief than face that nursery - especially since as the legendary thief she was likely to find a fan among the city’s nobles and be freed on some bond or work condition.

She took a breath, ready to scream in a very uncharacteristic turn from her usual stealth, when the pacifier slammed into her mouth. A huge rubber nipple pressed down on her tongue, and her eyes widened as she tasted something bitter and medical.

She kept waddling forward, while her hands pawed helplessly at the pacifier and found that it was impossible to move by her will, just like the diaper.

They hadn’t gone far when a huge pram rolled around the corner and down the street towards her. Its metal frame bent impossibly to lower the carriage towards her, while the diaper lifted her up from between her legs. She was deposited with a crinkle - finding that the bedding was plastic protected - and then the shade cover folded down. The diaper released its hold on her hips then, except then the blanket pulled itself tight over her.

The pram raced upwards. Their passage was almost silent, and Sienna didn’t doubt that there was something supernatural about their presence now, as if nobody could see them.

They stopped for a moment, still far from Lady Dimitrescu’s estate, and Sienna looked around hopefully from her place inside the carriage. Her vision was slightly obscured by the huge pacifier shield. Was somebody here to rescue her? A competitor to Lady Dimitrescu?

Only… The butt plug from earlier appeared at the edge of the carriage. Sienna’s eyes widened as it lowered itself down and crept beneath the blanket, while the back waistband of her diaper began to pull itself out.

There was a scream from within the carriage, and then it raced itself uphill.

Sienna thought that her night couldn’t get any worse, when she realized that a giant of a woman was approaching the parked pram. As the lady of the house leaned forward to check on her catch, Sienna saw that those impossibly large knockers were even bigger up close… What had Lady Dimitrescue said? Something about milk? Surely she was joking about that part…

“Well well well,”Lady Dimitrescue said with a smile, “What have we here? It looks like Mommy caught a little thief.”

Her face hardened. “Of course, I’m going to have to teach you that stealing is wrong. I think a good spanking should suffice for tonight.”

--- An unknown time later ---

Mommy entered the nursery.

Seeli always watched in awe from behind her crib bars. Mommy was so majestic. So strong. So powerful.

She shifted awkwardly in her diaper. Would she get changed before Mommy pulled down her top today? When she was held by those big hands under her dirty diaper, well, it was unfortunate. Especially after the efforts she made not to squish it all night, even during the occasional times when the toys came alive and made her play, before returning them all to their cribs and told them that the grownups would never believe them.

Of course, play sometimes meant riding on the seesaw, or even playing ‘diaper bumps’ on each other, so it couldn’t always be helped.

But tonight Seeli had managed to keep herself out of the awful mess in her diaper. Yesterday’s oatmeal, cookies, and special Mommy’s milk had resulted in a solid load, and it wouldn’t squish easily.

Nanny Gestelle reached her crib and lowered the bars, then easily lifted Seeli out.

She endured a sloppy kiss on her forehead with only a slight grimace on her face - any worse and she might earn the buttplug - then raced to line up before Mommy. The diapers often made her walk, but never for this. Mommy wanted to see that she could be obedient.

She endured the usual praise, kisses, and a diaper check. She waited eagerly while Mommy announced which of the girls would need immediate diaper changes. Gracie had had a massive blowout during the night, which delighted Mommy while she patted and squeezed the diaper to confirm that ‘poor Gracie’ definitely needed a change. Priscilla of course desperately needed a change, and only slightly blushed as Mommy squeezed her diaper and praised her.

Seeli waited hopefully as Mommy spoke, only for the giant woman to finish with only Gracie and Prissy. She and the other girls all shifted uncomfortably, and watched the enormous woman walk past them, with her enormous butt swinging at their eye level.

“Come along girls,” she snapped, making for the breastfeeding armchair.

Mommy was clearly disappointed with not enough of them proving what babies they were last night. Today would be an extra long milk session, followed by big bowls of oatmeal and prunes in the highchair, and then practicing their dance recital out by the lake while Mommy lounged in their picnic spot.

Seeli waddled after her, wondering whether today would be another day where she broke down and promised Mommy that she could do better. Mommy was reasonably impressed with her, the giantess had said so herself, but she still tapped Seeli on the nose and said that even though Seeli had stolen Mommy’s heart, she still had to steal her own naughty thoughts away, and then, Mommy said, she would be have proven herself as the greatest thief in the city. Just like she’d shrieked that she was on that first night, when Mommy had first changed her temporary magic diaper for something thicker while she tried to bargain her usefulness in other roles. Mommy had smiled, and said this was the best possible use for her, and now, well, Seeli almost couldn’t imagine it any other way.

Mommy was very wise and powerful after all. Her collection of special daughters was proof of that.

“Now,” Mommy said, pulling down her top and revealing those enormous, impossible tatters. “Who is thirstiest?”

They all shuffled about.

“Nobody? Very well.” Mommy clicked her fingers, and looked at the new girl. “Seeli. Come to Mommy right now little girl.”

“Yes Mommy,” Seeli replied, then waddled forward, trying not to be at least a little bit excited about those giant breasts.

As she got closer, Mommy pointed a finger at her diaper and then gestured up, and Seeli began to float up through the air suspended by her own diaper. She tried to keep the weight on the front to avoid the mess in the back.

Perhaps today would be one where Mommy didn’t hold her by a cupped hand beneath her her diap-

She winced as Mommy’s big hand squished the back of her diaper. So much for that.

"Oh you're a thirsty girl aren't you!" Mommy cooed, pushing Seeli’s head towards the massive teat with her free hand. "A thirsty girl. Thirsty wirsty. Oh yes she is. All blocked up with naughtiness and trying to be a big girl. All naughty. She needs her milk. So much milk. Oh yes she does. Yesh she does! Milky times baby!"

Mommy didn't even sit down, and carried her to the window while Seeli suckled.

It was hard to see with the mountain of flesh in her face, but perhaps Mommy was picturing how Seeli had looked zipping away out the window and the chase which had followed. Mommy often said it was one of her favorite memories.

She supposed it was a unique memory for her too. It had led to the next 24 hours which included her first rectal temperature taking, her first spanking, and her first realization that there was no chance of beating Mommy. In truth, the chase had just been a fun little game which Mommy had been playing with her new daughter.

After an age, Mommy pushed her away from the teat.

“Don’t steal it all you naughty girl!” she laughed.

She pulled down her top and revealed the other nipple.

“Now can you ask?”

Seeli licked her lips.

“Can I please have the other milk Mommy?”

“Of course sweetie.”

With that she shoved the thief’s face into her breast.

“See, isn’t it so much nicer when you ask for what you want, instead of trying to steal it? Mommy has made such a good girl out of you.”