I'm no expert but this is some rough editing which may or may not be better.
It was cloudy dreary day, -"It was a dreary cloudy day." There are rules in the ordering of adjectives.
the skies emptying themselves onto the landscape of concrete and metal, a manmade jungle to be sure, the jungle of Nerima. Those without means to prevent a soaking scurried along from one cubby hole to the next, trying to keep from getting wet; the lucky people who had umbrellas were able to see a rather strange sight.-skies emptied.
-Hmm, second sentence is too wordy imo.
"Those caught defenseless by the rain (It didn't occur to me that it was raining the first time I read it) scurried along from one cubby hole to another while the lucky people carrying umbrellas were piqued by a rather strange sight."
shadowed from above by an umbrella and yet not once getting wet despite the speed of movement;-I see what's going on here as I had the same problem when I started writing. This may hurt our egos a bit but sometimes the way we structure sentence, while it may seem stylistic actually is sacrifice for clarity when others read our writing.
"A young man carrying an umbrella dashed swiftly across the walkway, not once letting a teardrop touch him."
A punch, a kick, a block,-staccato is a perfect substitute.
"Punch. Kick. Block."
It would seem then that the people who lived here were at least somewhat used to strange occurrences, instead unperturbed that a panda and man are in fact fighting in the first place."It would seem then that the people who lived here were used to strange occurrences, unperturbed that a panda and man are fighting in the first place."
“I still think It stinks” the man cried “choosing a fiancée for me, I’m supposed to be a man aren’t I?”(As strange as it was for the man to start yelling at the panda, it didn’t prepare them for its reply,)<-remove this it's slows down the action.
some edit you may or may not like:
[it’s ][/it’s] the panda replied through a sign board then flipped it.
[you ][/you].
(The man obviously didn’t like that, evidenced by the fist in the panda’s face.) <-replace with "the young man punched him obviously not liking what the panda said" or something to that effect.
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You could rewrite almost all the sentences and I swear it'd be better. You don't have to be descriptive at everything.
The young man inhaled a handful of oxygen before kicking with his toes which were inside a black shoe flinging his body to the air while tilting his head to take a peek of the panda after him.
The panda took a wide step then a left step then a smaller right step. Inhale through the nostrils. The young man simultaneously exhaled through his mouth. The panda then rotated his shoulder axially to lift the weapon he uses which is a signboard made from mahogany by slaves of the king of egypt to hit the young man who is a meter above the ground.
There's a fine line where it would seem pretentious and annoying. I'm not saying you can't experiment with words and make it as you want it but it's a skill to take into account the impression it will make to the audience who are reading it for the first time.
Also you're writing action so the pacing needs to be fast. yes, the length of the words determines pacing as well. You could say.
"He inhaled. ' I don't like it pop.' his eyes staring at the panda's with ominous intent. He then lifted his hand with the umbrella and threw it off the ground as the water form heaven drown him in his form which was ready to fight."
You could be descriptive on slow actions or dramatic scenes.
However I got the idea that your action scene was supposed to be fast so:
“I still think it stinks,” the man cried, “choosing a fiancée for me? I’m supposed to be a man aren’t I?"
The panda lifted his signboard [it’s for family Honour!] then flipped it, [you will do as you are told]. The young man immediately punched him as a reply.
“Suck on that old man, I’m going back to china.”
The man was about to turn around and run off when the panda shoved a sign in his face. [I thought you were a man] the panda flipped the sign yet again [are you going to prove me wrong?]. The man stopped for a moment then growled at the panda. His face then became downcast. <-that's your chance to be descriptive.
“Fine pop, yah win, let’s go meet that friend o’yours”.
With that the man and the panda walked away leaving a large number of people nonplussed whom after a few moments, went on with their business. There were more things to worry about than a fight between a man and a panda.
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anyway all this typing is shoddy and stuff but I hope you get the main idea. Rewriting is the most important part of writing. I hope you could finish the work as the premise seems pretty cool.