We find our Zero Suit clad Heroine currently getting ready for a large scale contest, she had heard about this holding contest from one of her contacts and decided to get involved since the prize was a huge lump sum of credits and a all expense paid trip to a paradise world's finest resort.
Currently all the girls involved were told to drink and eat as much as they want before they start but whence they do there's no turning back. Samus gladly took part in the drinking since they were offering free beer, chugging down glass after glass of the stuff, feeling her bladder filling with each gulp thanks to her chozo DNA increasing her metabolism.
By the time the contest was to start she already had a bladder bulge the size of a grapefruit, which was being squeezed by her tight zero suit. Other girls however had even larger bulges thanks to their binge lifting longer and some even were already holding their crotches or even asses from the food. Samus whispered to herself, "This should be much easier...but I can't let my guard down. One slip and this suit is ruined...". She then followed the others onto the stage as they all had to take seats in chairs with no bottoms in them, almost like toilet seats.
And Samus quickly checking in between her legs spots a waterproof camera, which made her sigh and look around and sure enough, she could see monitors that revealed each girls lower area that would get soaked by even slight leakage. Once the whole opening ceremony bullshit was out of the way the contest actually began, Samus currently was rubbing her bladder bulge and crossing her legs to keep herself under control, while she did this she hears a girl whimper next to her, revealing that she had in fact already leaked out of stage fright, the leak showing up on camera thanks to her bright white panties.
Samus felt her bladder ache to join hers in at least a slight chance of relief from all the boiling piss trapped inside her abdomen. She then decided to just sure up her defense she slid a hand between her legs and clutched her pussy, feeling it quiver in her zero suit and her hand, making her bite her lip. Shortly thereafter a few girls cried out, scattered across the chairs but all doing the same thing, losing control and wetting themselves. Soaking Jeans or filling panties they couldn't stop it any longer from coming out in a terrible flood of either acrid piss or foul greasy shit.
This made Samus both long for a bathroom and cringe at the poor girls losing themselves. After another thirty minutes almost every girl had slowly lost control of either their bowels or bladder and were disqualified, Sans for Samus and one other girl. This girl had a bulge similar to Samus yet was still holding it tightly. Both now were looking at each other, studying each-other's holding style, Samus had kept the same crotch holding style the entire contest but the girl who we'll call "Hunter" was holding herself, and rubbing her bladder.
Both girls had leaked at some point, Samus' you could see that it soaked her pussy as Hunter's made her panties drip with piss. Both girls were determined to win, whimpering, moaning, and muttering words like "Gotta piss..." or "I c-cant hold it...". It was until a mechanical looking humanoid figure began clapping and cheering for Hunter like a doofus that she lost concentration, spurting once, then a full on stream began pouring out of her. Which now she felt both anger to the robotic man and shame to herself. Samus had finally won, quickly standing up she rushed off stage yelling out "Send me the credits I gotta piss!" As she ran to the restrooms to finally let out the trapped piss, and go on a nice and long vacation.