He is alive. She forgot. He is broken( On Hold)

The Book Of Black.

(Jonathan's POV)

I hear a few voices from the living room. I think they belong to Magnus, Alec and one another person. I go out and see a blonde boy with golden eyes. I knew it was Jace. I still had the memories from when I had the demon blood in me. He and Clary were dating but now she has forgotten all about him

Clary was talking about him a while ago. She told that he was just irritating.
"Hey," I said telling them about my presence.
"Oh! Sorry if we woke you up," Magnus exclaimed.

"It's alright. So why is Jace here?" I asked looking at him.
"I came here to find out about the warlock who erased Clary's memories," Jace said quickly.
"Can you tell me the warlock's name? I might know a thing or two about her. I still have my memories of when I was Sebastian," I said sounding serious.
Even back then when it was Sebastian, I was still alive but I was pushed back. I had no control over anything. The demon blood ruled my body. I knew everything. I knew who my body killed and targeted. I even tried stopping the blood but I always failed. One good thing was I  the training for a shadowhunter, acquired all the knowledge and everything else.

"It's a warlock named Minerva Stone. She has pink hair and her warlock mark is a purple cat-like tail," Alec said sounding calm.

I thought about it for sometime. The name had rung a bell in my head.
"Ah! I remember. Minerva Stone. She helped Sebastian since she was in love with him and his ideals. I guess she did this to Clary to get her revenge," I said.
"Good. Do you know anything else. Like where she lives," Jace asked as he jumps from where he is.
"Not sure but I like she is 7 blocks from here," I said scratching my head.
"You guys better get going, he might be right. That placed has all sorts of wards up," Magnus said.

"We will. Thank you," Jace said.
As Jace and Alec were about to leave I said,"Wait. Can I come too?"

"Do you know how to fight against a demon. I don't think so. So your not coming," Jace said the whole thing quickly without giving me a chance to reply and left with Alec who gave me an 'sorry' look.

"I could probably beat him myself," I told Magnus with a slight smile on my face.

Jace's POV
We left Magnus's apparent and went 7 block down. True to Magnus's statement this place had many wards but I could sense that some were broken.

Alec and I have our weapons out and we go into a ruined house. The door was already broken and so we're the windows. The place had a rotting smell. All in one, this place was disgusting.

We went in with complete caution. We we're in a long hall way day there was a door every three meters on both sides. I could bet that the hallway looked never ending.

I took the right side while Alec took the left side. I opened every door and took my time to examine every room. I wasn't gonna let pressure get to me and miss a clue.
I was in the 12th room, when I felt a demonic presence further down the hallway. I look at Alec and he comes by my side.

I was leading and Alec was just behind me as we took soundless steps. We reached want seemed to be the end of the hallway.
Finally, I thought.
But I soon realized that there was a glamour in front of us. I reactivated my rune and the glamour began to fade away.

I was in shock
In front of me was Sebastian chocking a pink haired women. He took out a knife and behead the women. I stood there not able to do anything.

"Hello brother," Sebastian said.
"Your not my brother," I said with disgust in my voice. I leaped towards him with my weapon in front of me. I aimed for his neck. While I was running towards him,  he didn't try to block the attack so I smirked to himself. As my sword was about to make contact with his neck, my attack was blocked by Sebastian.
How? I don't remember him being so fast.

"How about next time?" He said and with that his body turned into smoke and left through the window.

I stood in shock and asked Alec,"Could he always do that?"
"He did the same thing at Magnus's apartment. I think it's new," Alec said plainly.
"Come on. We need to go back. I'll tell Izzy and Clary at meet us in Magnus's. I really don't like the fact we are hiding thus from the Clave. If we are ever found out we are busted," Alec said before heading towards the exit.

I was about to run after him but looked towards the dead warlock once again and thought,'She was the only one who knew what happened to Clary. This makes things a little difficult.'

Just before I took off I notice a book next to the body. I picked it up. On the front cover was an elaborate design. It also said,'The Book Of Black.'
This might be important and Magnus might know something about this since it's a warlock's book. It reminded me of The Book Of White.