Quick backstory to this imagine because there's no part 1 and if I start where I want to start you guys will be lost asf:
You're Barry's twin sister (you guys don't look alike because you look like yourself because I said so), you guys are super duper close and you're both speedsters.
You're on a date with your husband, Oliver (aka my baby daddy) when Joe sends you an SOS saying Barry is being chased by the speed force and the only way to stop it is if it eats him.
You quickly tell Oliver what's going on and give him a long kiss on the lips before running to Central City to help your brother. Cisco gives you the rundown of what's happening and why. The entire time your mind is racing.
"So Barry's DNA needs to be inside the force for it to stop?" you yell over the raging storm that ignited flames on cars and buildings each time it strikes.
Cisco nods and you watch helplessly as your brother speeds away from the city bringing the storm with him.
"Can't you infuse something with his DNA and feed it to the force?" You yell tying your loose curls into a bun, preparing to run after your brother.
"I would need at least a day to figure it out we can't do that right now!" Cisco yells back.
"Anything that has his DNA will work?" You sigh losing sight of Barry.
"Theoretically."
"Breach him here."
"What?"
"Breach him here!" You yell frustrated and scared at the thought of losing your brother.
Cisco closes his eyes and focuses and a second later Barry is in front of you. You embrace him quickly and press a small kiss to his head before he collapses to the ground exhausted.
"Looks like I'm cleaning up your mess again, big bro."
He lets out an exasperated grunt of confusion but you're gone, taking off to the storm which has begun heading back. You approach the storm rapidly and as the blinding white hole opens you jump in.
Everything is still.
~
"She... she did it," Cisco pants astonished, while Barry scrambles to his feet.
"No..." Barry is about to take off running so he can open the speed force, but Iris puts her hand on his shoulder and he involuntarily sobs, "we need to get her back!"
He's hysterical and Iris just pulls him closer to her.
"She's my little sister!" Barry collapses to his knees and Iris goes down with him. "I'm supposed to- to protect her!"
"Barry?" Oliver is standing not too far away with his bow hanging in his hand, he can tell what's happened but he has a shred of hope that you're going to come running around the corner.