Just imagine with me a little:
Okarun from Dandadan being trained by Cheong Myeong from the Webtoon series Return Of The Blossoming Blade.
Bro is desperate to get stronger than his current self after gaining Turbo Granny's power cause he wants to be there to protect Momo.
What better way than to train under Mount Hua's most ruthless disciple? I'm 100% sure Okarun would get ridiculously strong under Mount Hua's crazy training regiment. He'd probably surpass Jiji's athleticism!
Think about the other characters' reactions when they hear that some top dog swordsman (more like mudskipper) from a martial arts sect deep in the mountains is training Okarun into getting stronger!
They might find out eventually (or a little sooner) how Okarun trains. Their reactions could start from concern to confusion, then shock.
The other Mount Hua disciples might even be more surprised than the Dandadan characters that Cheong Myeong took in his own disciple, and might even think: “Wow, he really is gonna take in a disciple of his own, huh? Well, my condolences to the new guy, he won't last a day...”
Imagine their surprise when Okarun didn't complain as much like the other disciples at Mount Hua because of the training. Cheong Myeong would be pleased to hear that the newbie is more determined than ever to train!
Since he plans to get stronger, Okarun would (to Cheong Myeong's surprise) take the fundamentals with serious focus and Cheong Myeong would boast about it with pride saying: “See this kid right here?! Yeah, that's my disciple right there! He's my student! I trained him!”.
I feel like the first time Turbo Granny and Seiko meet Cheong Myeong, they could probably tell that he's not the age he physically looks: A warrior veteran from a hundred years ago thriving in the physical form of a young boy no older than 20. Turbo Granny might even take a glance, turn to Okarun and say: “You should take up on training under this guy. You might just learn something from him!”.
I know that Mount Hua is known for it's training in the martial arts of swordsmanship, but since Okarun doesn't wield a sword, it could be possible for him to be able to mimic sword strikes and patterns with Turbo Granny's power, which makes me think:
He won't need a sword, because he is the sword. His body would move like a blade, his strikes are precise and fast, his stamina might seem limitless, and most of all, his aura might radiate the same deadly focus as a seasoned martial artist when transformed.
I say Cheong Myeong and every disciple in Mount Hua, including the Dandadan characters, would find it impressive and interesting how Okarun is able to engrave Mount Hua's sword techniques through Turbo Granny's power without even wielding a sword.
I have more to say, but I don't know how long I can stay up to do so. What do you guys think? Feel free to add your own ideas to this concept! Please tag me, I'm really curious to know about your opinions! :)