Next morning
In the Gremony manor.
Rias and her peerage are standing in front of Sirzechs.
Rias: You wanted to speak with us Devil king Lucifer.
Sirzechs: Thank you all for coming. Now the reason I've called you all here was to speak about Shun Sitri.
Rias: Okay?
Sirzechs: It about what happened to him 7 years ago.
Rias, Akeno and Koneko become interested.
Sirzechs then looks at Kiba.
Sirzechs: Kiba Yuuto.
Kiba: Yes, your majesty?
Sirzechs: Remember the hell hole you came from before we found you?
Kiba: I do sir.
Sirzechs: Well the same thing happened to Shun.
Everyone eyes widen in shock from what they just heard.
Kiba: What no way. Are you certain?
Sirzechs: *nods* 7 years we raided an abandoned facility where scientists were experimenting on children. Myself, Lady Serafall and Lord Rimuru were there at the time. We managed to capture many scientists, but unfortunately we were not able to save any of the children. We only managed to find Shun.
Rias and her peerage gasp, Asia and Akeno both cover their mouths.
Sirzech: When we found Shun he was using the last of his energy.
Sirzechs: Serafall was the one who approached Shun, but he was completely scared at the time. After Serafall leant his name she embrace and that cause Shun to try and get out of her grasp, which didnt work and caused him to fall unconscious. Which she then immediately took him to the hospital.
Sirzechs: I stayed behind to gather more Intel on what was going on, to say I was pissed would be a understatement.
Kiba: May I ask what it was they were doing my lord?
Sirzechs: *Sighs* They were using the kids as experiment to make them stronger and indestructible. Unfortunately every procedure they did it always ended up in a failure and each child lost their life.
Rias: By why?
Sirzechs: It was because their body reject it every time. Except for Shun.
Sirzech: Shun willingly chose to be there test subject and after 9 months of watching his friends died in his arms over and over again they finally made a success.
Akeno: I'm guessing they were able to create something indestructible.
Sirzechs nods.
Sirzechs: Remember those claws you saw come out of Shun knuckles.
They nod
Sirzechs: That is called adamantium, the strongest and most indestructible mental ever found, and Shun entire skeleton was turned into adamantium.
Rias and her peerage eyes widen again.
Sirzechs: So his entire skeleton is metal, but he also got a healing factor somehow.
Sirzechs: However I have recently learnt of something.
Rias: What is it?
Sirzechs: Eventually Shun will die from the adamantium.
Rias and the other gasp.
Rias: No that can be?!
Sirzechs: It true, but it will only start happening once he loses his healing factor.
Rias, Akeno and Koneko began tearing up.
Rias: *sobbing* Isnt there a way to prevent it?
Sirzechs shake his head.
Sirzechs: I'm afraid not. As much I hate it, there isnt a cure for it.
Kiba was shocked and pissed for what he just heard. Shun was going to die and there is no cure.
Rias: Does Serafall or Sona know about this?
Sirzechs: No, they do not. But I'm going to inform them once you have left.
Sirzechs: Shun willingly chose to be those scientists tool so that the other children would live, but it was no use.
Sirzechs: I ask that you do not ask about talk about the incident with Shun, he still PTSD from it.
Rias: *clenches his fist* I understand.
Sirzech: That is all, be safe on your way home.
Everyone bows and leaves the room.
With Rias
Everyone was processing what they just heard.
Rias/Akeno/Koneko/Asia: *thought* Shun...
Kiba gritted his teeth while clenches his fist.
Issei still couldn't believe it, Shun will die...
Timeskip
With Serafall, Sona, Rimuru and Yasaka.
Sirzechs: Thank you all for coming.
Rimuru: May I ask what it is you called us here for?
Sirzechs: I received information regarding about Shun.
Yasaka: What is it?
Sirzechs: I hate to say it, but Shun will die from the adamantium.
Everyone:
Serafall: *scared* Your joking right.........? Please tell me your joking?!
Sirzechs shakes his head
Sirzechs: I am afraid it's the truth. Scientists told me, that once Shuna loses his healing factor the adamantium will start killing him. They didn't say if the process will be fast or slow.
Sona: *tearing up* Is there a way to stop it?
Sirzechs shakes his head.
Sirzechs: I'm afraid not.
Serafall: *sobbing* Damnit......why him! What did my brother do wrong?! Why does he have to suffer?!
Rimuru pulls Sona, Yasaka and Serafall into a hug while they all cried for what they just heard.
Rimaru: Do they know when it will happen?
Sirzechs: No I'm afraid they dont.
Rimuru had mixed feelings about this. He was angry, sad, devastated and scared. But he face stayed calm.
Sirzechs: I am sorry.
They leave the room.
Sirzechs: *sighs* That was harder than I thought.
With Rimuru
Rimuru: *thoughts* How am I gonna tell this Milim and the Kijins. They see Shun as practically family.