An Adoption Gone Right

Why is this happening?

Percy POV
I ran out of Camp Half-Blood, tears streaming down my face as I did. Tears of anger, of helplessness. How could Poesidon do this? I thought. How could Annabeth and Grover? Even Tyson had turned his back on me. They all had. And for what? FOR WHAT?! A older demigod that had her head shoved up her ass? They had turned their backs on me because of her. All of them. Every last damn one. I hated them. Excellent! This is just what my life needs!

Harry POV
I'm not going to fight this war anymore. If the ones who want me to triumph for them put people in Azkaban without a trial I want nothing to do with them ever again. Maybe Voldemort really will change this world for the better. Focusing on the feeling of family I felt my magic whisk me away.

Percy POV
As I walked through the streets of Manhattan I could feel more and more monsters sneaking up on me. I wouldn't be able to hold them all off and live, but I couldn't find it in myself to care. When I looked over my shoulder I saw at least 50 monsters in the back of the alley, rushing towards me like an unstoppable wave. To the front, even more blocked the entrance to the street. My only escape route. I was surrounded and about to die. Uncapping Riptide, I wondered how Poseidon, I spat the name in my mind hadn't taken his sword from me. Then I remembered, I had left before he could. I smiled to myself I would be the last demigod to hold this weapon I would make sure of it. As I was about to begin hacking at the monsters just to see how many I could send back to Tartarus before they killed me. A teenage boy my age landed hard next to me snapping out a stick as he did.
I looked at the tiny stick he had and thought "oh what the heck. I've killed monsters with less ." His appearance wasn't promising though, tattered clothes, messed up hair and tired green eyes that held the look of someone with no one left to turn to. His scrawny frame didn't help either. I knew we were both going to die. Great! Perfect! Everything is wonderful! I thought until the kid levels the stick at a bunch of monsters and yells
"Reducto!" The army was slammed backwards. Maybe I underestimated this kid. Together we take down the monster army back to back until they all are dust going to Tartarus. We are about to congratulate each other when different types of monsters flew over our heads.
"Aliens?" I asked.
"I don't know." He answered.
"I'm Potter, Harry Potter by the way." He holds out his hand to me.
"Percy." I shake his hand deciding to trust him.
"Let's go kill these things!" He shouts yelling
"Stupefy!" As he goes, causing an alien to crash unconscious.
"Can you levitate me up there?"
"Sure! Wingardium Leviosa!" To my complete shock I begin to float upwards. When I get the opportunity, I grab onto a flying thingy slicing the head off the alien that occupied it. Ugly things these aliens are. While Harry fights them off from the ground I am leaping from one flying thing to another.

Harry POV
Percy's crazy! Oh well can't say I'm not as I take out more and more aliens I bring unwanted attention to myself. Someone fighting with these things diverts course and heads straight for me. I yell "Diffindo!" But he dodges it and keeps flying at me. I dodge into a back alley to narrow for him to fly in after me. His minions, I now realize have my alley surrounded. Percy tries to double back and help out but, is grabbed by someone in a flying metal suit. I don't want to know where he's going. Lightning suddenly strikes everywhere around me, driving the monsters back. A man comes flying in wielding a hammer. He grabs me, holding me to his chest as he shoots by.
"Let me go!" I yell at him as I struggle to get loose. He sets me down next to Percy?
"I see you got snagged too." He says.
"I wonder what gonna happens now hmm?" He turned to our captors as he said this. We are surrounded by people all with weapons pointed at us.
"You do realize that you are neglecting the battle here right?" I state.
"He is right Loki will not withdraw from the fight. Not even for the sake of his children." The man who grabbed me agrees.
"Who're his children?"
"You two of course. You possess his skill in magic, while the other has his skills with blades." He replied with a sneer.
"He's not my brother!" Me and Percy yell pointing at each other.
"You are just being a high and mighty godly bigot!" Percy shouted.