After seeing Ryueki's memories and all of his wrong doings, and plans. Kaneki, The Beast and Insect Familiars were intended to kill them.
But for some reason Kaneki stopped moving before he could start and summoned his mother's relic, one that resembles a guitar.
Chikao: Hey Sachi which relic is that?
Sachi: That's Demon Knight Hiragi- I mean Kaneki's Mom's Necro Guitar!
Natsuki: does it have something to do with the undead?
Sachi: Yes, from what I remember it's one of the most dangerous relics to ever be created.
Itsuki & Keiko: how come?
Sachi made a tense face and said.
Sachi: when played, it can summon souls that haven't moved on and make them fight alongside the one who wields the Necro Guitar.
Natsuki: That's terrifying!
Sachi: but there is also a downside to this relic, there is a possibility that it's user would get possessed by the souls they summon. From where I read Kaneki's Mom did got possessed in a few occasions in the past but was able to overcome those times very easily.
Chikao: but what about Kaneki?
Sachi: I don't know.
Natsuki: What is Kaneki thinking?
In the Higanbana residence*
Shino: Hey Kaneki! That's dangerous!
Yuuka & Miku: What is he doing?
Kaneki's friends and family were worried as they saw him with the Necro Guitar.
In Ruined Ryueki City*
Kaneki: let's begin.
♪~!
Kaneki began playing the Necro Guitar, it's loud music echoing throughout the ruined city.
Crack!
Thunder!
As Kaneki continued to play the guitar, cracks began forming underneath his feet, thundering black clouds formed above him.
Glow~!
Swoosh~
Followed by his visor glowing a bright red and his armor emitting a tremendous amount of black smoke.
Ryueki: HEY WHAT ARE YOU DOING?!
Ryueki felt uncomfortable, watching Kaneki play the Necro Guitar's music gave him an eerie feeling.
Ryueki's thoughts*
(What is he doing?! chest is feeling really heavy ever since he started playing that thing!)
Glare~!
(And it's as if... I'm being watched by more eyes)
Little did Ryueki know, the power of the Necro Guitar began to take effect.
Crack!
Swoosh~!
In no time, the black clouds became a portal, and.
Swoosh! Swoosh!
Hundreds of black and purple flames began coming out of it and flew towards Kaneki.
Kaigon: Young Kaneki! What are you-
Glare!
Kaigon, Ryugon & Hegon: !!!
The Three Ancient Beast Knights were intimidated by Kaneki, it was as if he was saying "do not interfere".
Swoosh~!
Thud!
Kaneki continued to play the Necro Guitar until he went on his knees as the souls of all of Ryueki's victims came and circled around him, until.
Swoosh!
Kaneki: Argh!
They all flew into him.
In Kaneki's mind*
Kaneki: There we go done.
???: Why?
After all of the souls went into Kaneki, he could now interact with them.
???: Why did you bring us here?
???: to that man.
???: ARE YOU GOING TO USE US LIKE THAT MAN?!
???: WHY DID YOU BROUGHT US HERE?!
???: IF YOU'RE JUST GOING TO USE ME THEN I'LL KILL YOU!
Many of the restless souls were aggressive as well not willing to cooperate.
Kaneki knew it would be dangerous if it continues on like this so.
Kaneki: I summoned you all here to make an offer and to help all of you.
???: DON'T JOKE AROUND! YOU'RE JUST-
Kaneki: Possess my body.
All souls: Huh?
The souls of Ryueki's victims were all shocked, they didn't expect Kaneki to offer his body to them.
Kaneki: Possess my body and take your anger out on the guy who had manipulated you and ruined your lives, I will not interfere until all of you are satisfied.
???: W-What? Why are you doing this?
One of the souls came to Kaneki and directly asked for his motives.
Kaneki: I've sensed all of your desire, desire to make up with everyone you had hurt when you were all alive, to apologize, all that kind of stuff. That's why hear me out my offer for a moment.
All souls: ...
All of the souls went silent, and with the silence Kaneki made his offer.
Kaneki: Good, here's my offer. You all have a choice now. once I grow and consume the second fruit of power, if you want to I could bring you all who want a second chance in life back to life or pass on to the afterlife once you all beaten that guy.
???: WHAT?!
Kaneki: I know you all don't trust me, considering your earlier aggression towards me. But be rest assured, I'm only doing this for all of you so you could either finally rest or have a second chance.
???: Why do you give us such an offer? We don't deserve it.
???: we're the ones who ruined our own lives.
Kaneki: ... Yes, that may be true. But I have a feeling you all will be forgiven by the people you had hurt. That and I could see your memories.
All souls: !!!
Kaneki: I'll be honest, I expected you girls to do the worst things possible like the girls who tried to attack my friends and family but you all didn't do anything remotely close to that. In my opinion you all aren't really that bad compared to the ones who tried to hurt my friends and family
???: Y-You?
Kaneki: Don't worry, considering these are very personal I won't show your memories. So? What will it be? Trust me and take your second chance? Or continue on with your regret and broken bonds?
The souls were all silent for a few seconds before giving their answer.
All souls: Fine, I accept your offer.
Kaneki: Heh.
Kaneki was happy that the souls of those girls had accepted his offer.
Kaneki: Contract complete. Now have fun with my body for the time being.
Burst!
Kaneki had given them complete control of his body after making the contract.
Kaneki: Oh but please not hurt my friends in the process okay? And don't abuse my powers!
With that, the victims of Ryueki has now full control of Kaneki's body.
Burst!
The souls: Grrrr RAAAAAAAAAH!
Black and purple flames bursted out as the souls have taken control.
Ryugon: Young Kaneki! Don't worry I'll-
"Let them rampage"
All 3: !!!
With Kaneki's order, the three Beast Knights didn't interfere.
The souls: RAAAAAAAAAH!
The souls then began to rampage.
Crack!
Spread~!
The opened the wings that were on Kaneki's back and flew high.
Extend!
Burst!
Bang! Bang! Bang!
The souls began sending out many projectiles all over the ruined city, before yelling in a very loud and distorted voice.
The souls: ITADORI-KUN! YOU'RE DEAD!
Hearing the combined distorted of the girls that he moved used, Ryueki felt a lot more afraid.
Ryueki: S-Stay back!
ROOOOAAAAAAR!
He created more flesh familiars to counter them, but unlike Kaneki who was just playing.
Snap!
With a mere snap of Kaneki's fingers, the souls turned the flesh familiars into dust.
Glare~!
Slash!
Rip~!
They then sent a slash towards the ground tearing it in half and creating a portal.
Ryueki: AAAAAAARGH!
Rip!
At the same time, Ryueki was once again turned to a portal.
Hegon: let's go!
Ryugon & Kaigon: Yes!
Swoosh!
The 3 Ancient Beast Knights left the ruined Ryueki City.
The souls: Here we come~
Followed by the possessed Kaneki.
Swoosh!
After they passed through the portal, the portal closed and Ryueki's two halves got back together.
Ryueki: Tch! HOW DARE YOU! YOU'RE ALL NOTHING BUT LOWLY SIDE CHARACTER-
Swoosh!
Pierce!
Ryueki: H-Huh?
Before he could finish, the souls controlled Kaneki's body and used his arm and thrusts it into Ryueki's body.
Grab!
Grip!
They then grabbed his leg and began to mess Ryueki up.
The souls: RAAAAAAAAAAAAH!
Slam!
Slam!
Twist!
Drill~!
Blast!
The souls were mercilessly beating Ryueki, slamming him the ground, using Kaneki's powers to twist and turn his limbs and innards.
Turning Kaneki's fingers into drills and using them to make holes in his body while blasting him with very hot fire.
All while healing him at the same time so we wouldn't end up dying.
After a while they had stopped.
The souls: we are now satisfied... You better keep your end of the contract.
Swoosh!
After they were satisfied, they left Kaneki's body.
Ryueki: Haa~! Haa~! It's over!
Ryueki thought it was all over.
Kaneki: OI I STILL HAVE A BONE TO TAKE OUT OF YOU!
Ryueki: !!!
But Kaneki was still planning to play with him.
Kaneki: HELLO SOON TO BE CORPSE!