Akio : Father!!
Seeing that the attack come from his father Akio was shocked and also upon the slash he feels his father's killing intent that's why he was shocked.
Akio's mom also see her husbands action and was in daze then suddenly Yukio say's.
Yukio : Akio you are very strong you can also able to conquer that sword than show me. if you can go toe to toe with me I will complete your one wish.
Hearing his father's word Akio was obviously very happy from inside but don't show it on his face And replies
Akio : Ok, But remember your promise you will have to fullfill my one wish.
Yukio : I will never break my word and in this fight to give you respect as a swordsman I will use my full strength.
Akio : Alright, so let's go to a more isolated space.
They all go to a non populated island with no vegetation it was a desert I land with rock hard surface.
Everyone was exited because they also want to see the fight of these two monster's.
Yukio pulled out his sword which was an unknown sword but Akio knows that sword very well it was Dante's sword "Rebellion" when Akio saw that sword he knows why his father known as strongest swordsman.
Yukio : This is my sword "Rebellion" which is also our family hair loom. now show me how much strong you got in these past years.
Akio pull out his sword "Yamato" and take fighting stance like Vergil.
Both of them release their conquerer Haki and sky suddenly split in half with clash of those two's Haki pressure was so hight that even for three Marines around them it become hard to breath Sengoku and Akio's mother released their conquerer Haki to protect everyone but some pressure was still their.
Then suddenly Akio use Soru with cat walk and suddenly disappeared from his place and try to mask his presence with his Observation Haki but Yukio was very strong and his fighting experience was also very high. he suddenly move and block Akio's attack while countering him with his kick covering his leg in Armament Haki.
Akio dodge his attack and took few steps back and reach out his hand on his blindfold and remove it while opening his two eyes with blue color they glow like star's in dark night.
When everyone saw this they know fight is getting very serious. in their previous clash they both are testing eachother's strength now thery are going to fight for real.
Akio covered his sword in pitch black Haki which is not shining. whoever know Haki can easily tell that it is a very high level of Haki.
Seeing thisYukio also covered his sword with Haki which was as dark as space. He suddenly moves his hand flexibly then send 4 slashes towards Akio which he countered very easily and sent 5 slashes towards Yukio which was to distract him then Akio use his fastest Speed and appeard in front of Yukio with his while slashing his sword flawlessly also adding affect of hasshokan.
But Yukio who can fight Whitebeard in his prime take that attack with 5 slashes with some difficulty.
When their sword collide ground beneath them crack like spiderweb while countering Yukio use his sword technique and slash toward's Akio which he block very gracefully.
Both were not using their full strength but by their Collison you can see Akio was being pushed in a hard spot by Yukio because his lack of battle experience.
Then suddenly to finish their small spar both of them stop fighting then take distance between them.
Yukio was first to move and release his sword aura which was dark red flames covering ground with flames heat and rose instantly in the area and Rocks stat to melt around them everyone could not stand the heat of his sword aura and they instantly move away from fighting sence And lock the area with their Observation Haki.
When Akio felt the sword aura of Yukio he also release his own sword aura which was golden in color and make sky dark and start heavy rain fall from sky which become vapour because of heat of Yukio's flames. Golden lightning covered the sky.
Both raise their sword and Yukio's flames take a shape like phoenix which is covered in red dark fire while Akio's Sword aura take shape like a dragon Covered in golden lightning.
Both slash their sword toward's each other both sword aura clash together which caused a huge explosion entire area was covered in fog.
When fog disappeared we can see Yukio and Akio standing Above the see using Geppo. while the island they were fighting on disappeared like it never existed.
Everyone was in horror because of power of these two monster's.they both stared into eachother's eye with serious expression but they also know that duel is ended.
They put their sword into their sheath and got on the deck of ship which was docked near the island while chating happily then suddenly Akio's mom appeard behind them and give both of them a fist on their head and scold them for fighting so recklessly.
Everyone seeing this sence start to laugh and atmosphere suddenly become serious to happy. Then Yukio ask.
Yukio : Tell me Akio what do you want for Your one wish.
Akio : I want to come a Pirate!!!!!
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Thanks for reading guys.😃👍
I know I can't write fighting sence of very high level.