It was a relatively normal day in Star Labs. There was no particular Metahuman activity to speak of, so things were pretty calm. Barry decided to use this unprecedented time off to take some time to experiment with his suit. Specifically, he was trying to replicate the ring stored suit the Reverse Flash used. He thought he had it more or less figured out, but he would need some help making the final adjustments. And with Cisco out of town, he'd have to resort to asking Harry. Fortunately, travel between the Earths was relatively commonplace now so he headed down to the Star Labs basement to breach over.
Meanwhile, on Earth 2, Jesse Quick was preparing to enter her own breach to go visit Earth 1. She had been a superhero on Earth 2 for a while now and had gotten pretty good with her speed powers. Even so, she often found herself looking to Barry for help with new situations. This was another one of those occasions, so she decided to pop over to Earth 1 and see if Barry was around. She too headed to her breach chamber, clad in her full Jesse Quick costume, and prepared to enter the breach.
Unfortunately for Barry, both speedsters entered their respective breaches at the exact same time. This had never happened before, and it had never occurred to any of the Star Labs team that this was something they'd have to worry about. As it turned out, it was not something that the Speedforce handled very well. In order to prevent the two speedsters from colliding, the speed force twisted and warped the corridors between worlds, fighting against the momentum of the speedsters hurtling towards one another. Unbeknownst to Jesse, she was redirected back towards Earth 2 by a forced U turn in the interdimensional space. This was still considerably better than what happened to Barry. Wanting to minimize his chance of colliding with anything, the speed force took him down a rather funnel-shaped path, decreasing his size along the way. Unfortunately, he reached Earth 2 before a corresponding path had time to grow him back, and only a few seconds before Jesse did.
Barry was thrown out of a breach, landing face first on a cold tile floor. He managed to climb to his feet to wonder about where he had ended up, only to be interrupted by-
BOOM!
The ground shook as huge objects struck down on either side of Barry. He was thrown onto his back by the force of the impact and suddenly realized that these were not two objects, but two gigantic red boots. And high above him, where the enormous legs coming out of those boots met, was the titanic butt of fellow superhero Jesse Quick, clad tightly in the red leather of her costume. As she stood powerfully above him, he felt as though he was standing at the base of the statue of liberty, though this giant lady was red rather than green. He didn't know how, but somehow the breach had to spit him out shrunken on Earth 2. And it seemed Jesse was in the breach as well, though she seemed to make out just fine size wise. As Barry realized he would need to somehow get her attention, he was glad Jesse's costume didn't include a skirt. He didn't want to make this situation more awkward than it was already going to be.
Of course, Jesse had no idea about Barry's presence on the ground. She was too focused on the fact that she had somehow ended up back on Earth 2. She'd never had something like this happen before. It's not like the breaches usually required you to steer or anything. She turned back to the breach to have another look at it, only to watch it begin to shrink before her eyes. Just like when Cisco closed breaches on Earth 1, it dwindled in size until it completely imploded, cutting off any connection between their two Earths.
"Well, that's weird..." Jesse muttered, not really sure what to make of the situation. She took a step towards where the portal had been, but there was no indication it had ever existed.
Barry was concerned about the breach's bizarre closure, but much more concerned about the giant red boot swinging over his head. He darted to the side easily, relieved to find he still had his speed. Of course, given his much smaller stature, he covered much less ground on each step. He still felt the shock wave as the boot slammed down in front of him, but he managed to stay on his feet. He quickly rushed in front of her, only now getting a good look at just how massive she truly was. Her gigantic legs and ass only made up the lower half of this Titaness, and she truly towered over him when he could see all of her.
"Jesse! Down here! It's Barry!" Barry yelled, hoping to get the giant brunette's attention. Unfortunately, he was too small to have his voice heard at this minuscule size. If he was going to get her attention, it wouldn't be from yelling on the floor.
1. Jesse's metahuman alarm notifies her of a metahuman presence, and she notices Barry on the floor.
2. Jesse thinks Barry is a bug, and stomps on him with her full speed, causing Barry to phase in panic. He ends up phasing right through her boot and ending up pinned under her bare foot inside her shoe
3. While Jesse is trying to figure out what went wrong, Barry decides to climb her to get her attention.