3rd POV:

After Y/n has been revived but his appearance have changed dramatically, Y/n came up with a plan for the engagement party of Rias Gremory and Riser Phoenix. The first part, Chisato will inform Sona about the news of Y/n's revival in secret along with the evidence of his murder that took place in the Rating Game on hold until the time is right. Lastly, Y/n and Kuroka are planning to investigate the proof of her innocence at her former master's place. So they agreed to his plan and started in motion.

Kuroka and Y/n have arrived at the old abandoned building of her master's home. It was covered in dust and spider webs that covers the entire furnitures. They have reached to the library, noticed the dried blood from the master of this house by Kuroka, but with a good reason. He noticed a certain bookshelf and hears the wind drafted through the gap. He destroyed the bookshelf with his awakened powers revealed an secret passage that leads downstairs, she casted some magic to brighten the stairway and started to walk down. Another door is in front of him, he repeated the same method.

As the door's gone, it revealed that really shocked Y/n to the core that he sees a room with cages and inside them was filled with rotten corpses and dried blood. Y/n is starting to raise the crimson aura in rage for which horrific events of cruelty.

Y/n:(anger):That monster...he's lucky that he's already dead...

Kuroka:(serious)Yeah, that's the real reason for my actions.

Then he noticed that another door at the end of the hallway, they proceeded to investigate there. It reveals the room filled with some lab equipments, tubes, a computer and a bookshelf full of books. It contains all of the illegal informations and experiments of every species. And Y/n noticed that there's a certain book reveals about Kuroka and Shirone. All of this horrific events definitely will clear Kuroka's name, so they recorded everything in this house as the second part of evidence. So they returned back at their home to be prepared for the engagement party.

(Timeskip to Engagement Party)

All of the guests are at present, Rias and Riser are in the wedding dress. All of the ORC members are here including Sona. Issei have objects that arranged marriage with his Boosted Gear on. Surprisingly, The Devil King, Sirzechs Lucifier former heir of the Gremory Family also the husband of Grayfia Lucifuge and the father of Millicas Gremory. The eldest child of Zeoticus Gremory and Venelana Gremory and the older brother of Rias Gremory.

Riser:(surprised)My lord, what's the meaning of this?!

Sirzechs:I've watched the game, but I'd say it was underwhelming. So I brought him as an extra entertainment.

Riser:But this is the final result of that victory.

Sirzechs:You there, Issei Hyoudou. You possess the power of the dragon. This party could use a bit more flare as the main event. So I decided to give this another chance against Riser, what do you say?

Issei:(grins)Alright I will-

*Gunshot*

A gunshot is heard, went towards to Issei's shoulder bleeding out. All of the guests are shocked and confused of this unexpected event.

Issei:(screams in pain)AAAARRRGGHHH!!! WHAT THE HELL!!!

Riser:(confused)Now who dares interrupts this affair?!?!

???:(firmly)...I did...

Asia:(shocked)That voice...it can't be...

Rossweisse:(smile)Yes, no doubt about it.

(Plays this song for this moment)

As they begin to hear multiple footsteps, most of the guests are confused by who they are. While Rias, Riser, Sirzechs, Grayfia and the ORC Members are shocked to see them. Out of the shadows revealed as Y/n Shirogane(Awakening State), Kuroka Toujou and Chisato Hasegawa are walking to towards them in serious expressions.

Y/n:(jokingly)Hey...why I wasn't invited? Because of my good looks?

Kuroka:(giggles)Darling, maybe because they didn't call us for invitation.

Chisato:(closed smile)Good thing we had friend who called me for the extention of this special occasion.

Sirzechs:(shocked)What!? Why is this human and the S-Class Stray Devil is here?!?!

???(voice over):(serious)I was the one who invited them.

That voice reveals as Sona Sitri in a formal dress. But surprisingly enough, Serafall Leviathan is here them.

Serafall Leviathan, formerly known as Serafall Sitri. She is the former heiress of the Sitri Clan and the eldest daughter of Lord and Lady Sitri, and the older sister of Sona Sitri. She a beautiful girl; looking in her late teens with black hair, tied into twin tails and blue eyes. She also has a child-like body (albeit with large breasts).
Unlike her serious younger sister, Serafall is cheerful and possesses a childlike personality.Adding to her childlike personality is the fact that most of her lines end with a star. She also has a deep sister complex, and has a tendency to get her sister into embarrassing situations.
Despite her childlike nature, Serafall can also be selfless and determined.

Sirzechs:(surprised)Lady Leviathan, Lady Sona? Why are they here?

Serafall:(serious)So-tan have informed me about the news of him being mysterious eliminated from the Rating Game. So I decided to come here to see of the confirmation...(blushes,smile)Y/n, what are your wishes?

Y/n:My first wish...Rossweisse and Asia Argento will be free from the peerage of Rias Gremory!

Rias, Akeno, Kiba and Koneko are shocked from Y/n's request, adding to the fire, Issei is very furious for taking his dream away.

Sirzechs:(neutral)Care to explain why?

Serafall:(serious)Everything will be explained after Y/n's match against Riser Phoenix.

Riser:(shocked)What!

Y/n:My second wish...Kuroka Toujou will be clear charges of her innocence with the evidence of our possessions!

Kuroka started to smile when Y/n made that wish. But when she saw her little sister Koneko (Shirone), Kuroka is furious from the inside when she knew of what she did.

Y/n:My third wish...Sona Sitri, she will be watching over Kuoh Town under her protection. While she can supervise Rias and her followers as well!

All the audience from the engagement party are shocked from Y/n's request. Serafall, Sona, Asia, Rossweisse, Kuroka and Chisato are helping very happy for him. While Sirzechs Lucifier and Grayfia are very curious about this situation, which will be explained everything after the battle.

Sirzechs:(neutral)Very well, we will grant your wishes. After this event, we discuss this at the meeting with Gremory Family and Sitri Family.

Rias/ORC:(shocked)What?!?!

Riser:Well then, this is getting interesting battle for the both of us.

Y/n:Yeah you're right about that...(summoned the Crimson Rebellion)

Sirzechs:Grayfia, if you will...

Grayfia:(bows)Yes, my lord...

Y/n and Riser has been transported to the battle arena for the match to begin.

Riser:(smirk)Riser will not lose this fight to a pathetic pawn...(wings appear)

Y/n:(grins)Well I'm not going to lose either too...(battle stance)

After a minute of silence showdown...
Riser and Y/n began to charge each other and clashes with their powers. Y/n did a three combo and ends with a powerful thrust. Y/n began to push Riser back, as he was struggling to fight back.

Riser:(confused)What...what kind of power have you hidden from me, pawn of Gremory?

Y/n:(serious)That's something that you have the right to know very soon...

Riser is confused by his statement...

Riser:(confused)What do you mean by that?

Y/n:(serious)Well, I will show you then...

Y/n began to them by releasing the crimson aura and lightning effects surrounding around his body.

From the ballroom, most of the guests are confused by what power did Y/n released, but Sirzechs, Grayfia, Serafal and Chisato somehow recognize that power.

Grayfia:My lord, that power is-

Sirzechs:(neutral)Yes, I know but it's too early to say.

Serafall:(surprised,blush)Wow! Y/n-kun is super amazing.

Chisato:(mind;serious)That's no power of an ordinary devil...but a demon from the old legends.

(Back to the arena)

Riser:(shocked)What!!! Impossible, that's no power of a devil!!!(emitting dark aura)I'm the Great Riser Phoenix will not lose to the like you, I'm the immortal!!!

Y/n:(mind;serious)He's not in his right mind, I have to find a way to him before he causes havoc to the other devil kinds.

...Awaken your power of your heart...
...Manifest your power of the Keyblade...

Y/n:...Come forth, Rebellion's Oath!

Y/n's Crimson Rebellion begin to brighten and transformed into a Keyblade called Rebellion's Oath.

Y/n:This is my power that awakens within my heart...(smile)now it's show time!

(Begin battle music)

Riser begin to cast barrage of fireballs, as Y/n was dodging them easily. Y/n and Riser has clashing with their powers. But it's useless for Riser because he's been pushed back not been able to fight back. Y/n have using his speed to three hit combo and finish him by a swift slash through him. Y/n's final attack when his weapon started to glow red with lightning effects and swing a vertical slash. Riser began to notice that he doesn't have any strength left and his regeneration powers are not responding. At the same time, his dark aura begins to fading out of his body.

Riser:(pain)...I-Impossible...how can...this mortal...be so strong...(fainted)

Y/n's keyblade have reverted back to his Crimson Rebellion for a while and walking towards to Riser.

(End battle theme)

Suddenly, his little sister Ravel Phoenix is protecting Riser.

Ravel:Stop!!! I won't let you hurt him. He's my family, my big brother!

Y/n stopped himself from fighting, began walking towards her. Lord and Lady Phoenix started to worry about Ravel and Riser, but they saw of what they didn't expect from Y/n. He patted her head to comfort her while she was shocked and blushed of his actions.

Y/n:(smile)You made your point, Ravel. The match is already over, due to your selfless act of bravery and caring. I knew your brother is really important to you and the entire family. I have fought Riser to the sake of my friends and my loved ones. I have fought out of respect and trust. Promise me to take care and support Riser as his little sister, in return he will do the same for you.

Ravel:(smile;surprised)I promise I will.

Y/n nodded, as for Lord and Lady Phoenix are very happy of his action but Y/n sees an red orb attack coming behind them...

Y/n:(shocked)Look Out!

Y/n grabbed both Ravel and Riser Phoenix to a safe distance from that attack and they were shocked to see who is responsible of that.

Y/n:(serious)So you have some balls to show up and attacking them off guard, haven't you Shitsei Hyoudou.

(To be continued)

(A/n:Well that's all he wrote for this story. Now Issei dares to enter the battlefield without some second thoughts. But soon, their true colors will be revealed to all of the guests including Sirzechs and Grayfia of the ORC's act of crime. Stay tuned for the next chapter of Third Sparda of Fairy Tail. Enjoy reading.)