Noya Hienma

Noya「ノ夜, lit. Of night」is a high ranked possession-type demon of the Black Demon Series. He forms a contract with Guren Ichinose in Seraph of the End: Guren Ichinose: Catastrophe at Sixteen and becomes his weapon.

Appearance
Noya is described as a beautiful 12-year-old boy with milk-white skin, scarlet hair and eyes that match, and a pair of horns sprouting from his hair.

Personality
He is playful and mocking such as repeatedly calling Guren "cute" and takes joy in tempting him with desire and power. He also teases Guren with a countdown and says that he will become a demon soon enough anyway.

History
According to Noya, he was once a human before becoming a vampire that has lived for so long that he had lost track. At some point, Noya turned into a demon and got sealed into a weapon as part of the cursed gear development.

Book 3
Guren finds a demon sword at the end of a road which was thrust into the ground next to a running motorcycle. Desperate to become powerful to save his friends, Guren grasps the sword and loses consciousness.

Book 4
Guren hears a voice calling his name and awakens in a completely white space in his heart. The demon Noya tempts him with power and approaches him. He chats about Mahiru and says that Guren will turn into a demon regardless of whether he accepts that power or not. Guren touches Noya and willingly gives up his humanity, leading Noya to mock him for making the wrong choice. He says it is unacceptable for a human to give up on his humanity while he is still human. Everything goes black, and power overwhelms him.

Guren wakes up with the sword in his and a motorcycle next to him. He hears war going on all around him but no longer feels any pity or empathy. His desires encourage him only to kill, and he mutters about needing a sheath to suppress the demon's will before getting onto the motorcycle.

Although he loses control after killing all of the Thousand Nights members in the school, Kureto was able to restrain the demon and his squad saves him. After the restraints are put on Noya, Guren continues to use him in many battles, and eventually asks Noya to become his friend.

Book 6
Near the end of the book, Guren can unleash approximately 30% of Noya's power while maintaining control.

Forms and Abilities

 * Demon's Thrall: Noya can enter it host's dreams and memories to create nightmares and break his host's will in order to take over his body.
 * Basic Form: Noya takes the form of a black katana.
 * Possession: Noya possesses his host to grant him immense strength and power as well as enhanced healing and senses while filling him with desires. The more desire his host has, the greater his power becomes.

Book 4
"Hello, Guren."—To Guren, Chapter 1 The demon took a step forward. Inky blackness spread beneath his foot. "…" As the blackness spread, Guren had the sense that something precious in him had disappeared.—To Guren, Chapter 1 Guren felt the words’ seductive pull.—To Guren, Chapter 1 Guren’s eyes widened in surprise. But it was too late. Blackness. Everything went dark. And relentless power surged into his soul.—To Guren, Chapter 1
 * A voice spoke in the darkness.
 * "'Hijack' makes it sound like I’m doing something wrong. I’m here because you wanted me, Guren."—To Guren, Chapter 1
 * "It makes me very happy that you want me," the demon said, smiling. "You desire power, don’t you? You couldn’t have chosen better than me ♪ Once we get inside each other, you’ll be stronger than you could have ever imagined."
 * "Oh? But we’re going to be so close. We’re going to be together for the rest of our lives. You should say my name, too. It’s Noya. Go on, say it. Speak my name, and I’ll give you a night of overwhelming carnal pleasure."—To Guren, Chapter 1
 * "Guren," he said. "Look at me. Look at how close I am. But I want the last inch to come from you, Guren… Want me, Guren. Hold me. Give your mind and body over to me. Then… you’ll be able to protect them all." The demon smiled sardonically.
 * "Well? Are you just going to run away again? Say that you’re not prepared to make your move yet? That the timing isn’t right? I like humans who’re like that, too. The kind who can run away shamelessly when it’s their own skin on the line. But you’re different, aren’t you, Guren? I already heard that you were different."—To Guren, Chapter 1
 * "You’re just so lost, and gentle, and weak, that it’s hard not to love you. Once we join together, our strength will be unstoppable! …There’s no need for us to hurry, though. It will happen sooner or later. You’ll become a demon. Even if you don’t touch me today, you’ll reach out for me eventually… They’ll all be killed, because you weren’t able to protect them… And then you’ll turn into a demon out of absolute despair. That suits me fine. Either way, it’s too late to stop. You can’t help but turn into a demon. We’re already intertwined."—To Guren, Chapter 1
 * "Aha, Guren!" Noya shouted in rapture. "Wrong choice ♪ You’d think it would be obvious, but humans should never give up their humanity? You really didn’t know that? You’re so adorable!"
 * "--Next, let’s save Mito, Noya said. What will you do if they’ve raped her? I bet it would feel good to punish the rapists? How about if she’s been killed? I bet it would feel good to avenge her. There’s so much fun to be had in the human world! I can’t wait until you and I are one, and I can finally be set loose!"—To Guren, Chapter 2
 * "Really?  But I thought you were the loner.  I mean, you’ve never believed in anyone.  That’s why you sought me out.  Because no one else would help you."—To Guren, Chapter 4

Book 5
"Once, I was a human. "Once, I was a vampire. "And now, I am a demon. "What do you suppose I’ll become next? "What will I gain by causing you to fall and transform into a demon? "That’s what you want to know. Isn’t it? You’re in a pickle now. All out of clues. If you’re ever going to find Mahiru, you should probably listen to what I have to say. Don’t you think?"—To Guren, Chapter 5
 * "Don’t, Guren. I don’t want you touching any other demons… You belong to me. There’s no reason for you to mess with other demons."—To Guren, Chapter 3
 * "Don’t judge a book by its cover. Demons appear in their most pure, undiluted form, from when their desire was at its strongest. So I guess when I was most dewy-pure, and felt the most invincible, I must have looked around…"—To Guren, Chapter 5
 * "Once, I was nothing.
 * "You’re damn stupid, you know that? You shouldn’t trust a demon so easily."—To Guren, Chapter 5
 * "Don’t get all sappy on me, with that stupid look on your face. It’s embarrassing, you know… having somebody want you as strongly as that…."—To Guren, Chapter 5

Book 6

 * "Act as nice as you like, Guren, but the real you is still waiting inside… There was a demon living in your heart long before I ever got here. You always wanted to bow to no one, always wanted to have it all. Remember when you were a child, and you thought that all of your dreams would come true? The truth is, you still feel that way now… The kind of dreams that normal people would have given up on long ago, you hang onto like a child. You want these things so badly you can’t help it, not even if you have to hurt someone else to get them. I think that must be what Mahiru likes about you…. It’s what I like about you, too, Guren. Poor baby, someone killed your daddy. And now you’re trying so hard not to seem angry. Not to cry. Look at you, laughing, playing games with your friends. But all this time… all this time you’ve been thinking of ways to turn the whole world on its head."—To Guren, Chapter 2
 * "I bet other demons don’t have such demanding masters…"—Grumbling about Guren, Chapter 3