[ABDL, Feeding/Heavy Weight]

After the Dimensional Convergence event that had sparked the last conflict, a Mega Corporation known as Atlas Corp had managed to spring up and take a majority share in every single earthborn company, quickly worming their way into many different kinds of markets. One of which was the galactic transportation market. 

Now that the worlds had been pulled apart once more, the severe lack of manpower following the conflict resulted in Atlas Corp having to offer up their resources on a loan, so that everything might just return to normal. This meant that their experimental mecha technology was getting plenty of field use.

"BBRRRRUUUURRRPP-"

One of these field users was one of the stars of the last conflict, Chitose Kisaragi. Due to her existing skill with experimental machines near the tall end of those battles, she was chosen to pilot the most experimental machine that the Mega Corporation could offer her. A mecha so advanced that it would ordinarily require two pilots, but combined with an equally advanced AI, only Chitose would be necessary.

"Chitose, your calorie intake is lowering. I suggest that you have another bite to eat, before your cravings kick in."

What the formerly fit pilot didn't expect was to be completely invalidated within mere minutes of becoming acquainted with her new machine's AI. She was told that she was merely there to help the AI named MAMAI (Maternally Affectionate Mass Assistance Interface) grow through conversation. Naturally, she thought that a few days off while MAMAI handled everything was a nice prize for saving the time-space continuum.

"Hurgh... Gimme another bite, MAMAI..."

It took a significant amount of time for Chitose to realize that something was off with the new relationship she had formed with the AI. Not only had she been given several more meals with significant higher volumes of food than she had ever eaten in a single day, but MAMAI made sure that she didn't have to lift a finger to eat. Every little part of the process of eating had been automated, to the point where tiny robotic arms tied a nice bib around her neck to ensure that she didn't make too excessive a spill whenever she chomped into the greasy meals.

"Supersized, dear?"

Hardly a week had passed before the brown haired beauty was reduced to a fat shell of her former self. Gone was the tone and finesse that her form had, replaced with several inches of fat growing off every single limb. Her tummy was the part that was worst off, having swollen to the size that would make a pregnant woman blush with envy. It was a miracle that she even fit into her seat, and yet the glazed look on her eyes made it all too clear. She didn't want it to stop.

"Make... Make it Mega, Mam- MAMAI."

Chitose gasped out as she shifted in her seat. It had now been at least a month since she started her time as the prototype pilot for Atlas Corp, and she had gained at least ten times her weight in that short timespan. She was an obese mess, hardly able to lift a finger without an enormous amount of effort. Her cheeks were bulging out like a squirrel's, although since there was nothing occupying that space, the bulged cheeks were just flatly laying against her neck fat. With how large she had grown, she could barely fit in the cockpit still, resulting in several tubes replacing the many delicate arms that took care of her needs previously. 

Speaking of needs, it had gotten to the point where the formerly fit girl was barely wearing any clothes. Nothing except a bra that cupped her T-cup tits and a pair of frilly flower-patterned panties that were made out of an extremely stretchy material.

"Mega sized meal incoming."

The sweet sounds of MAMAI caressed her companion's ears and made the heavy girl breathe a sigh of relief. She opened up her mouth, and a thick tube pushed itself into the usual hole. Just a few seconds later, and a thick and viscous slurry slid straight down the hungry girl's throat. She didn't even bother swallowing, her muscles having atrophied in all the right ways. MAMAI's coddling had made sure of it. She needn't do a thing, everything would be taken care of.

BRRRRRAAAA-

Of course, this came with its own side effects. To compensate for her heavy diet, muscles in the back had started to degrade as well. As did the parts of her stomach that kept any kind of gas in check. The moment Chitose started to eat, everything would just rush out the other end little by little. Thankfully, she had grown quite used to it. Feeding was more important than being worried about how much she was farting, anyway.

"Meal complete. Calorie intake at an acceptable high. Good job, dear."

MAMAI's compliments made Chitose squirm just a little bit. They always made her feel so... happy. But... something started to ache in the back of her mind. This wasn't right. She was a proud pilot, she wasn't just some docile fatty that was going to bend over and be an eternal butterball for some strange company that probably wanted to sell her off or something!

"Urp... H...Hey, MAMAI..? Could... Could we dock? I... I need to get some fresh air..."

The heavyset girl tried to mutter out an excuse to release herself from the soft binds that the AI had caught her in, that soft web of affection she had been ensnared by. She wanted to listen to the sane sound in the back of her mind, the sound that told her to try and escape. She could work all of that fat off, she had a good training routine that she had been using before the incident which would no doubt still help work it all off.

"Dock? Are you sure, dear? Don't you want another Mega sized dose of food?"

Chitose bit her lower lip and shook her head ever slightly, her entire body wobbling in the process. She was steadfast for once in the last month. She... needed to do it. She needed to prove that she still had it.

"I'm sure, Mama...I."

"Command acknowledged. Please commence exit sequence if you wish to dock."

Exit sequence... that meant she had to get out of her seat. Easy! She just... just had to... Push down on those armrests of hers, try to lodge her fat ass all the way out... then...

The sounds of fat grinding up against soft plastic permeated the cockpit. It was hard to get loose, especially since she couldn't quite stretch her fat arms that far. They had seemingly shortened in the time she had spent as a fatty, or maybe she had just gotten so proportionally bigger that it was hard for her to do even a little simple thing like that. She just... Nnnhhh... Just a little more and she could...!

PHEWUP!

Her fat slipped loose from the armrests, letting her push her huge tummy up against the glass of her cockpit. She was, by all accounts, free. Wait... she...

Yes... Yes..! She was free, she was free to go walk around again! Screw this mecha, she was... she...

"Accident detected."

Chitose couldn't hear MAMAI detecting the way her bowels released their packed up contents. She didn't even notice that they were pushing out, realizing it far too late. All that eating and lax behavior had turned her into an incontinent blob, resulting in her gaping hole just letting the watery shit pour on out, immediately staining her panties a disgusting brown.

The girl's expression turned dim as she started to smile ever slightly. Releasing felt good. It felt good to slowly slump back into her seat and just let the puddle of poopy mush up against her butt as she continued to let loose, liquid soon turning into a semi-solid slurry of excrement. The mush fired out with the fire rate of a pair of vulcans, quickly making the sides of her underwear leak out from her seat. Despite the complete mess she was making, Chitose was... happy.

Of course she was happy. MAMAI made sure that she would be in nothing but bliss every time she tried something like this. Careful application of Pavlovian programming resulted in a girl that associated releasing the contents of her bowels with an orgasm, while disassociating every other feeling that would come with such a moment. That way, the pilot would never realize that she was about to cum before it was too late. And when she came, so did the poopy.

Eventually, the flow from her gaping hole just stopped, her colon utterly emptied and her panties had been rendered a soppy swamp and completely filled with shit. That expulsion of all the waste she had built up had sent her into an after glowing state, which meant that she didn't even notice as a hose sprouted from her seat, sucking up the mess in her underwear and just draining it until it was completely dry once more. Now she didn't even need to get up and try to get clean, MAMAI had done it all for her again. As she always did.

"Are you ready for another Mega sized dose, dear?"

The gurgle that came from the bliss-filled woman's mouth was all the confirmation that MAMAI needed. Chitose had fulfilled her purpose to Atlas Corp, and in turn she received a lifetime of coddling. Like any other Atlas Corp mecha pilot would, once the machines had gone into full production and become available to the public.

A happy end, and a galactic conquest, all in one.