That Time I got Reincarnated As A True Dragon

What is a Demon king

While anos and Avis was going on with their duel Rimuru who was supporting this spell suddenly felt some third party was interfering.
She with her eyes enhanced looked at the source and found that someone was trying to bind the Necron sisters back to their destiny. Why is he doing this ?
Rimuru doesn’t know why , but she didn’t like it when someone is manipulating someone’s life like a puppet . This person reminded him of claymen. And brother she knows how much that guy is a control freak.
So without anyone noticing she gathered some void energy to her fingertips while also infusing some energy form her Ultimate skill. Like she was drawing a horizontal line she cut the other party who was interfering with the spell .
she vaguely heard the scream of “ Curse you outsider “
‘ hmm why is that voice seems familiar ‘ after thinking for bit she shrugged and thought,
‘ meh he must be a pain in the ass if I forgot about him. Oh looks like  anos is finally getting a little bit serious‘ thinking so she looked at them and sure enough there was  Avis kneeling on  the  ground and Anos was holding something she found nostalgic .
It has no define shape as it changes it form to suite its wielder. The sword that is the manifestation of Destruction. The sword that a few knew about .
Venuzdonoa, the Abolisher of Reason. A sword that destroys order . The nemesis of the Gods. One of the reaming God Slaying swords in this planet.
“ hahah so what if I am not God. I am the Demon king the person who rules the demons. Since my subordinates wants to see a miracle then I shall show them .” saying so Anos started to walk towards the God who is now fully fused with Avis.
“Foolish . Do you still think of yourself as the demon king, stupid founder? No one believes in you!
And do you really think you can defy the order that we gods rule ,  preposterous  know your place mortal “ saying so Avis and the god both rushes towards Anos while swinging both  sides to cut anos in half.
Anos dodged one and caught another one with his bare hands. The time authority tried to manipulate his time but every attempt was met with this failure .
“ What is a demon king? Is it power? A title? Authority? A position?”
“All of it.” Avis shouted as he tried to move the scythe.
“It’s none of them. I am simply me. To completely annihilate those enemy who rise up and rebel against  me no matter what their destiny or providence is. That is what a demon king is.” Anos shouted as his < demonic eyes of Destruction> activated sending a wave of Destruction that pushed Avis away.
“ Etch this scene into your very being Avis for I am the Demon king of Tyranny and I am back “ with those words Anos swiped his sword and destroyed Avis’s and Eugo Ra Raviaz’s sources together.
“ noooo curse you Anos Voldigooooooooood “ with their last scream both of them were annihilated.
With his part done he put away Venuzdonoa away. He then turned to see Sasha and Misha fusing with their past selves. And turning to the side he saw Rimuru with a small smile on her face.
“so did you found  why your creation is not following your orders “ she asked a rather strange question but anos replied,
“ yes  it seems like someone has killed him and fused another source with his weakened one . But unfortunately I couldn’t analysis it as it was destroyed too quickly. “
“ hmm this may get more messy. You see when you were fighting I felt someone trying to interfere with the spell. “ said Rimuru as she looked at Anos seriously.
“ that’s troubling but ohh well I doubt they will leave a trace for us to investigate. So I’ll just leave this to Avis . “  sais Anos as he shrugged his shoulders.
“ Ohh that guy survived “ asked Rimuru a bit surprised. While she doesn’t have any experience but the feeling having some one forcefully occupying one’s source is quite painful. Most would be dead in seconds.
“ yeah whoever did this Is  actually is quite talented at  source manipulation. Avis source was spared from the attack completely. So I should be able to revive him when this is over. Hopefully we may have a lead to the master mind “ anos said as he looked at the Necron sisters who now done with the fusion.
“ hmm looks like they fused without any problems. Well what do you say we head home  I’m starving “ said Rimuru as he handed the fallen scepter to Anos.
“ hmm you are right if we arrive at the outside before morning we’ve be able to get a perfect score “ Anos said as he looked at Sasha and Misha with a smile and then started to leave with Rimuru.
“ hey wait up  we are coming too  and why the hell are worried about grades when you are the Demon king and all “ said Sasha as she and Misha ran to catch up with them.
Anos looked at a with a smile and said,
“ hahaha since this is my first time participating in such an exam so I should definitely have a perfect score don’t you think so . “
Rimuru at the side thought ‘ yeah at that time there was no one who could have the mentality to even conduct such tests. ‘
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“ we are back “ said Rimuru happily as she entered Anos’s house with the rest of the team.
As usual after they gave their spoils to the teachers for the authentication test they all decided to crash at Anos’s place to party.
And with Isabela’s hyped attitude they were soon greeted with various kinds of dishes. 
As they were enjoying the happy atmosphere Rimuru suddenly froze for a few minutes. Then her face turned into a scowl but she quickly hid it.
Anos who noticed her odd behavior looked at her questiongly . Rimuru sensing his gaze created a Telepathic link with him.
‘ Anos I will go out for a while try to distract them from my disappearance’
With those words she teleported away leaving Anos speechless . But he quickly casted a illusion magic to cover her. He cursed inwardly,
‘ shit what happened for her to disappear without even making a good enough excuse ‘