He put the book down on a table beside him and pulled out a paper clip. He twisted it so it was shaped like an S. It then changed into a perfect replica of Backbiter. I pulled out my own sword. And then we started to duel.

PPOV:

He was good, but I was better. We were running up and down the isles of books. At one point, I could have sworn I heard Athena in the back of my head 'No! Not that book!' she had yelled into my head as he sliced an ancient book in half.

Over the course of our fight the Thalia and Katerina ran in. They were about to help when they saw who I was dueling and they both froze. So far, I had the upper hand; then again I was in my father's realm. We kept fighting, I was sending wave after wave of water at him, and he managed to keep fighting only with his sword.

It kept going, on and on. There was no end, only close calls. We were too good. Neither of us could defeat the other. But he was smarter. Half an hour after we started fighting, he lunged. Just not at me. He flew through the air aiming directly at Katerina. I couldn't stop him; there wasn't time.

I closed my eyes, waiting for my sister's scream. It never came instead came the sound of sword hitting sword. There standing in front of Katerina, was Luke, with the first backbiter blocking Nick's copy.

"I don't think so." Luke said, deadly quiet.

The two of them began to duel. I pulled Katerina into a hug, watching their fight over her head. Now, I may have been in my father's realm, but Luke had been training longer, was a better swordsman and as far as I knew, he still had the curse of Achilles. Soon, Luke had Nick pressed against a wall. Luke's backbiter was at Nick's throat.

"You do not touch her." Luke growled.

"I can touch her if I want, she's my girlfriend." Luke looked over at Katerina.

"Can I?" She nodded. He turned back to Nick. Katerina hugged me tighter and buried her face in my shoulder. And then Nick's head fell to the ground, shortly after his body fell.

Katerina let go of me and walked over to her dead boyfriend's body. Luke walked over to her. I saw Thalia shoot me a look. When I didn't understand, she pretty much pulled me right out of the library. I knew that in Thalia language that either meant, 'I am going to kill you and don't want people to see' or 'I need comforting, but no one could know'.

Almost as soon as the double doors closed, she fell into my arms sobbing. I'm not sure whether it was over the death of her brother, the fact her brother was the traitor or the fact that Luke killed her brother. Either way, I held her in my arms, not saying anything, just letting her cry, which in this case, was probably best.

KPOV:

I ran into a library as I heard the clanging of swords. I hadn't seen Luke in forever. If he was hurting one of my boys he is worse than dead. I pulled out my sword but froze when I saw the sight before me. Yes Percy was there. Yes Percy was fighting. No, Luke wasn't the other fighter. The other fighter was Nick.

I stood frozen in my spot for five minutes, just watching my boys duel. Then Nick got smart. He took in his surroundings and he lunged, straight for me. I had no time to re-act. No time to think. I bet if there had been time, I still wouldn't have thought or moved. I would've just stood there frozen. Which is exactly what I did.

I watched the sword grow closer and closer, my battle reflexes, refused to work, but still slowed things down. It came closer and closer until it was right in front of my neck. And then another sword connected with it.

"I don't think so." Luke said, deadly quiet.

The two of them began to duel. I was still frozen, Percy pulled me into a hug, I watched their fight over his shoulder. Luke had been training longer and was a better swordsman so Luke had Nick pressed against a wall quickly. Luke's backbiter was at Nick's throat.

"You do not touch her." Luke growled.

"I can touch her if I want, she's my girlfriend." Luke looked over at me.

"Can I?" I knew what he was asking, 'Can I kill him?' was the question. I couldn't speak so I nodded. He turned back to Nick. I hugged Percy tighter and buried my face in his shoulder. I didn't look as I heard the two thuds.

I waited a moment before let go of Percy. I walked over to Nick's be-headed body. All I could do was look down. No emotion came. No sadness, no pain, just numbness. Through the haze of my mind I noticed Thalia and my brother leave and Luke walk up behind me. I turned to face Luke.

"I'm sorry I mistrusted you. You saved my life. Thank you." I said. He held out his arms. I practically threw myself at him. I buried my face in his shoulder and sobbed until I passed out. But I remember from before everything went numb and black, the feel of security of his arms wrapped around me. I loved the feeling. It made me feel safe, and after this ordeal, safety was what I needed.

LPOV:

I had promised not to kill anyone. I had promised, no matter what, not to kill anybody. But I just couldn't let her get hurt. I couldn't. I had just walked in. Everything slowed. He lunged for her. I lunged too. He couldn't hurt her. I wouldn't let him. Our blades connected.

"I don't think so." I said, scary calm.

Then I let instinct take over. I wouldn't let him hurt her. She can't get hurt. I won't let her. That was all that I could think. Somewhere I was aware of her hugging Percy. I knew that as much as she was mad for him attacking her brother she still loved Nick.

"You do not touch her." I growled.

"I can touch her if I want, she's my girlfriend." The boy said with an arrogant smirk on his face. If he has touched her in anyway, I will meet him in Hell and kill him again.

"Can I?" I asked Katerina. She knew what I was asking, I could see it in her eyes, she nodded. I turned back to Nick. And with one swipe of the blade, Nick was dead.

PPOV:

Thalia had cried and cried and cried. The tears just kept coming. Eventually she fell asleep, but guess what, even in her sleep she cried. When I felt her body slacken, I picked her up and held her like a small child. Fun fact for you, even though Thalia is all fierce and scary and can kill grown men easily, she is freakishly light and easy to carry.

I leaned against one of the pillars and waited for Luke and Katerina come out. I thought about the prophecy,

'Conclusions jumped to. A man accused. A traitor revealed.

A friend lost, Olympus to preserve or crumble with a single choice.'

I had immediately thought the traitor was Luke when Atlas had told me about the traitor. So that would be the first two parts. Then Nick was revealed as the traitor. Nick was lost as a friend. Now comes the last part. Great.

Luke walked out of the library with Katerina in his arms. The funny thing was, I didn't flip out. I could tell that he was enjoying it more than he should, but I didn't care. I don't know if it was that I liked Luke better than Nick or the fact Luke just saved her life. Either way, I didn't care.

"Her too?" Luke asked, indicating Thalia, sleeping in my arms.

"Yep." Was my response. I noticed that Luke had the glowing book in his hand and he was supporting Katerina with one arm. I knew Kat was light, but not that light.

With that we set off towards the elevator and with in minutes we were reunited with the rest of our group.

"Oh my gods! What happened to her?" Nico yelled. It was a good thing the park had long closed and we were the only ones in the park, or else there would have been a lot of staring.

"Nothing. She just passed out." I said, handing Thalia to him. Now, she just passed out may seem like a big deal to some people, but in demi-god world (especially with a child of the big three) that's nothing.

"Percy! Oh my god!" Annabeth yelled, throwing herself at me. Apparently they really had returned. I wrapped her into a hug. We only broke apart when I felt a tug on my jeans. I lifted Katie up.

"Your okay!" She exclaimed, hugging me.

"I hope you're not disappointed." I laughed. She shook her head. I put her down and turned to Bianca and Clarisse. They were both sleeping in a corner, some lookouts they were.

"Percy?" A voice came. It was groggy, like it was just waking up. It wasn't Thalia, so I turned to Katerina. I walked over to where Luke was holding her. I went to take her, but she just held onto Luke tighter. "I'm sorry." She said, looking at me. Now I know what Annabeth means when she says 'those eyes can get you anything'.

"For what?" I was confused.

"For bringing him into camp. On the quest. I should've known. I grew up with him. I should've known." Katerina sobbed into Luke's shoulder.

"Kat. Thalia and Annabeth brought me right to camp. Thalia went as far as sacrificing herself for Annabeth and I. Annabeth had been my best friend since we found her when she was seven, yet I betrayed her. It is something I regret everyday of my life. The point is, no one can see betrayal coming, even a daughter of Athena." Luke told my sister. I don't know if she already knew this or if it just didn't matter much, but she didn't react, except for her tears slowing until they stopped.

"Luke, can I talk to you?" I asked. He looked wary, but put Kat on a bench next to Nico and Thalia. I walked with Luke until we were on the other side of the castle.

"I'm sorry." he rushed out as soon as we stopped, "I shouldn't hold your sister like that."

He was so worried. I laughed. "Dude. That's not what I wanted to talk about, yet." I paused. "I wanted to say thank you and that I was sorry. You saved her life. You can hold her however you want, as long as she is okay with it. Also. I'm sorry for jumping to conclusions and assuming you were the traitor. You knew it was Nick since the beginning, didn't you?"

"I did. That is why we were so cold to each other. He was worried I would tell and I was worried he was going to hurt one of you. And on the other subject. I'm like twice your sister's age." He said. I hadn't thought of that.

"Well..."I thought, "Technically Thalia is a lot older than Nico, but that doesn't stop them. Plus you were re-born, so technically you are only like a day old... either way. I approve. I think she needs someone who will watch out for her. And I've seen the way you look at her, you deserve her. I know that look. It is how Nico and Thalia look at each other. It's how Nico say me and Annabeth look at each other, 'like idiots in headlights' was his way of putting it." I laughed at the last part, but the rest I said truthfully and sincerely.

"So..." Luke said, "You really approve?"

"I never thought I would say this, since I didn't know I had a sister and I kind of hated you for betraying us, no offense, but I completely approve of you dating my little sister." I said.

"I don't think it matters if you approve. It matters if I approve though." We both spun around to face the castle.

There standing in the middle of the archway, hands on her hips, glaring at us, was my little sister. The one and only girl who can kill just with looks, and with the intensity of her glare, I was surprised Luke and I weren't dead yet. She walked up to us, glaring the entire way. She turned to me first.

"I cannot believe that you need to give permission and that you do so without asking me!" She yelled. I shrunk under her glare. Then she turned on Luke. "And you! Asking my brother when you could have asked me! I mean really?"

Luke looked uncertain. "I've known your brother a long time, I didn't want him to hate me. Plus, I didn't know what you would say..." I had never seen Luke look sheepish, but I was seeing it now.

"I'll tell you what I would say, you idiot!" Her voice got louder and louder!

A.N. Review! What should Katerina say, yes or no? Forget about the age difference, I don't care, after all the gods are multiple thousand years old and Percy's mom was in her twenties or thirties.