What if Tanjiro was a Pure Saiyan? (DB X KNY)

The Slasher

"He reached the building and met up with the Mugen Train and stared at it."

-3rd Person POV-

The crow perched just under the ceiling beam while Kyojuro uttered, "The Mugen Train... I see. Though faint, the trace of a demon remains." Another man, who seems to be the train's maintenance crew leader called out, "Hey you! This place is off-limits!" Kyojuro says, "Hey! I was sent here by the Railway Bureau to deliver these bento boxes." The man finished cleaning his hands and yelled behind him, "Hey! He says he brought us bento!" Rengoku placed the bento on a box as everyone started to crowd him. The maintenance leader passed a box and told him, "Hey, take one to Tatsu. He's resting in the office." Kyojuro asks, "Why was the Mugen Train brought here?" The man laughed and looked at the train while saying, "Right, when there's no way it's a problem with the body. Word on the street that it's a man-eating train. You don't know how bitter that makes us. So now that it's being put back into service, we want to do all we can to get her back into shape and send her back out into the world." Kyojuro dropped his smile and asked, "Back into service?" The man said, "Yeah, tomorrow night. That's why we're all here-" Kyojuro felt a demonic presence emerge as a man screamed from the back. Kyojuro instantly ran to the back. While running, his crow screamed, "Demon! There's a demon here!" he saw a demon with its back turned. He unsheathed his katana by just a bit as the demon turned around. The demon held a child and said, "Oh!" The demon pierced the kid's cheek and body as he bled. Two maintenance members come from behind as the leader yelled, "Tatsu!" Kyojuro ordered, "All of you, step back!" Tatsu called, "Chief!" Kyojuro said, "Let the boy go!" "A Demon Slayer? How arrogant," said the Demon. He caught the scent of the bento and said, "Ugh! What's this stench?" The Demon then stomped on the bento box, destroying it. Kyojuro got slightly irritated as the Demon said, "Ever since I became a demon, I can't stand human food. It's so disgusting. Kyojuro said, "That bento was made with love by people I know. I can't just ignore that." The Demon said, "If it's revolting, it's revolting. Hey boy, your blood smells like it might be revolting, too." The Demon pressed harder on the boy's wounds, causing him to bleed more. The Demon added, "I'll just devour the humans that seem tasty, but the ones that taste bad... I like to show myself a good time by tormenting them all night!" Kyojuro said, "So, that's what this is about, Slasher? I find you offensive." "If you don't like me, then..." the demon began to move faster than anyone in the room could follow. "...let's see you slash me!" Most of the maintenance crew left in fear as the Demon finally stopped. He said, "No one's ever been able to stop me. I'm the fastest... of them all!" while he talked, Kyojuro tried to slash the demon. The Demon stopped again as he said, "Hey, sorry about that. You can't bring yourself to slash me with this kid in my arms. Should I be considerate and just kill him off?" The boy said, "H-Help me!" Kyojuro says, "Don't worry! I'm going to save you, no matter what!" Not on your life. Just yesterday..."

-Yesterday-

The Demon cut a woman's cheek and body. He took off when he started to get bored of doing so.

"I slashed this other woman until I was sick of doing it."

The Demon then took off just before Kyojuro and two Kakushis showed up.

-Present-

Kyojuro said, "I see. Now I know how fast you are. But I wouldn't get cocky if I were you. Last night, we thought you'd fled because we showed up, but apparently, you never detected us. It's true that you're quick to escape at least!" The Demon said, "What?" Kyojuro added, "We were able to treat your victim from last night right away. She'll recover without even a single scar." The Demon laughed as he said, "Even if she does survive, she's doomed to be consumed by fear for the rest of her life." Kyojuro says, "I won't let that happen! We're going to treat the wound o her soul, no matter how hard it may take to heal them, for as long as it takes!" The demon chuckled, "I'll show that self-righteous face of yours a thing or two. I'm going to kill that woman again!" Kyojuro said, "We're keeping her hidden! You'll never find her!" The Demon's smile dropped as he looked at the bento box. He smiled and said, "All right, then those bento vendors..." Kyojuro says, "They have nothing to do with me!" the Slasher recalled his words and said, "But you know them, right? Those are station bento, right? I can find out where they're from." Kyojuro leaned forward a bit as the Demon warned, "Don't move!" Kyojuro said, "You do offend me, you know." The Slasher said, "Well, I'm enjoying this! If you want to save them, then get to the station before me. Before that happens... I'll have to kill this one!" Kyojuro leaned forward a bit and longer at the Demon, slashing its arms off and freeing Tatsu. The Demin quickly ran away as Kyojuro caught Tatsu before he hit the ground. The Demon watched as Kyojuro caught the child and ran outside. He said, "I'll be going on ahead." He started his run toward the bento store at the station.
Kyojuro wrapped the boy's wounds as the Chief said, "Please... Please save him!" Kyojuro said, "It'll be okay. Just leave it to me. Also, my friends will be coming soon. As he said that, a couple more Demon Slayers followed his crow as it cawed, "This way! This way! This way!" A female Slayer said, "Rengoku-sama!" Kyojuro asked, "Where's the medical squad?" She said, "They're on their way." Kyojuro informed, "I've given him first aid. I'm leaving the rest to you." Kyojuro ran outside and came to a stop as he looked down the railway. He took a big breath as he took off again. While running down, he mentally used,