Firecracker (Bakugo twin x Kirishima) Soulmate AU

Training

Kirishima POV

After a while of jogging I finally get to where I met with Katsumi yesterday when I see her fighting somebody with spiky hair the same color as hers and eyes just like hers, I assumed it was her brother so I watched until they were done. He attacks first with a right hook that she easily dodges and kicks in an attempt to throw him off of his balance. He grabs her leg and flips her but she spins midair letting her land on her other foot. He releases her leg only to throw another punch at her face that she dodges, but the punch is quickly followed by one to her gut. She takes his fist after he swings again and pulls him forwards and as he stumbles she kicks him in the back pushing him to the ground. He then notices me and throws a shirt at her from their pile of stuff on a nearby bench because she was just wearing a sports bra and shorts. She hasn't seen me yet so she yells "We aren't done training yet Katsuki, I need to get better!" He stands up and yells back "Put on your fucking shirt, your boyfriend's here!" She then notices me and quickly pulls on the workout tank top before greeting me.
Katsumi POV
"Hi Kirishima! My brother decided to tag along today so we did some quick sparring before you came." I quickly explained before motioning towards Katsuki.
Hello, I'm Eijiro Kirishima!" Kiri said while holding out a hand for Katsuki to shake. He quickly shook it while mumbling "Katsuki Bakugo" just barely enough for Kiri to hear. After a few seconds of silence I decide to speak up "So, are you ready to train?" "Yeah, sure!" Kiri excitedly exclaims, to switch Katsuki says "Before we train fight me." Kiri is startled by how he so casually said it. "What?" Kiri asks still confused. "I said, fight me. If you can't even hold your own against me without quirks training with both of us would be a waste of our time." I was about to intervene when Kirishima responded. "Let's go then! It wouldn't be very manly to turn down a challenge." They quickly got into fighting stances and I yelled for them to start. Katsuki immediately charges with a right hook and it lands right on Kirishima's face. He didn't seem too phased, he must have a high tolerance for pain because I could see he was bleeding. He quickly threw a kick at Katsuki's stomach but it didn't phase him and he kept throwing punches. Eventually after a few more minutes of fighting Kiri got tired out and faltered in his step allowing Katsuki to punch him down and say "I win, but you held your own for a while. You can train with us for now." I walked over and helped Kiri up and while patting his back I said "You did pretty good, that punch to the face at the beginning looked really bad." "Oh, yeah. I have a really high tolerance for pain so it wasn't that bad." Before I could say anything else Katsuki interrupted with "Stop flirting with my sister and get ready to train!" Now both of us had a pink tinted to our cheeks while inyelled back at him "Shut the fuck up, if you want to train then go do something!" After that we end up training for a few more hours before Kiri and Katsuki leave as I continue my training. At around 3 PM I am finished and decide to go to the park I always talk with Toshi at because I haven't seen him in a while.
(Next chapter Katsumiearns that Toshi knows the secret she's been keeping)