Kit Rook is the son of Apollo. And a Herondale.

Chapter two

Kit was good at being sneaky. From his practice at the shadow market, when he'd blend into the crowd and walk in the darkest parts where no one could see him. Basically, he had always been invisible.
Until now.
It had just been him and his step father for so long, so Kit never really had anyone to watch carefully and notice when he was not there.
If you're wondering, Will went to live with at camp half blood two years ago after the war, when his miraculous talents in healing made him the best combat medic camp half blood had to offer. He's tried to persuade Kit to come, saying it wasn't safe for a Demi-God to be alone, but Kit had ignored his brother's comments. He could take care of himself. Plus, he couldn't leave their dad alone.
But now he left me alone, Kit thought sourly as he tip toes through the institute.
Today was training day, and Kit was ever so reluctant.
He was not looking forward to this at all.
Slowly, Kit pushed opened the door to the training room. Inside stood all the Blackthorns, the Rosales, and Emma Carstairs. Emma radiated with furious joy of getting to train Kit. A woman, Diana, was waiting impatiently with her hands on her hips.
"I see you took your time Christopher." She said.
Kit cringed. Having these shadow hunters say his name was far to intimate. The only people who could get away with that we're his step father and Will. Maybe Percy and Chiron, but that was about all.
Livvy and Ty came to Kit's sides.
"Hey," Livvy smiled, her dark hair was twisted into knots to keep out of her eyes.
Kit muttered a hi back.
Kit looked to see Ty already looking at him. He looked as excited as Kit felt.
"Are you going to answer me?" Diana said stepping her feet impatiently.
Kit blinked. "What?"
Diana huffed. "I asked why you are late."
"Diana," Julian said. "Lay off, it's his first day."
Diana snapped her murderous eyes to him. "Go to hell." She said, annoyed.
"That's why I'm late." Kit said. "I tried looking for hell, but I'm already here."
Emma snorted as Diana rolled her eyes.
"Today's assignment," she said turning around. "Is rafter falling. Landing on all fours from the highest of heights."
Julian stepped in again. Kit felt a rush of displeasure of seeing Julian stand up for him, "Kit can't-"
"I can." Kit said automatically. It was a reflexive answer.
Diana's eyes glistened in amusement. "Well then. You heard him. Go."
Kit narrowed his eyes at her stubbornly and started to walk when Ty said: "but- he hasn't had any training, he could-"
"He said he can." Diana interfered.
"But-"
"Ty." Livvy coed, she grabbed his brothers hand. They shared a sibling look, and Ty calmed down a bit, but still looked ruffled.
Kit didn't know how to react that the shadowhunter seemed to care about his safe being. It was unsettling.
Kit looked at the metal rafters. With a grab, he started to climb easily. All those summers at camp half blood really paid off.
Once he got really high, Cristina shouted: "that's high enough Kit! This is an exercise, not suicide."
Kit doubted shadow hunters knew the difference.
Kit pushed himself onto the plat form and looked down. Everyone looked up at him, expecting something. It was most likely failure. But Kit wanted to prove them wrong.
"Alright Kit. Land on all four in a crotch." Diana called.
"Diana-" Julian said again, but Kit already jumped.
Like some of the ares kids had taught him, he tucked and rolled on the ground. A pain went through his back, but he stood up anyways. He was sure if he'd had a sword, he'd most likely impaled himself. Clarisse would not be amused.
Everyone blinked in surprise that he actually pulled that off.
"Hmm." Diana said, looking Kit up and down. Kit scowled at her.
"Where'd you learn that?" Livvy said incredulously. She'd let go of Ty's hand and walked over to Kit. Kit shrugged. They all looked at him curiously, making Kit feel smug. He liked having a wave a mystery around him, an aurora that would tell people they wouldn't be able to solve him because he's unsolvable. He's unknowable.
Someone started to clap in the distance.
Kit turned and saw the infamous Jace Herondale, leaning and smirking, bestowing his grand presence onto them. Kit rolled his eyes.
"Well done," he said. "As expected of a herondale."
Kit rolled his eyes again.
"Jace," Emma said excitedly, like they hadn't seen him that morning.
"I agree," Diana says and pats Kit in the back. "I think he's going to be exceptional."
She looked at him like she was trying to make a moment, like she was trying to seep being a shadow hunter onto like seeping him into cool water. Kit kind of appreciated it. Everyone else was dumping it on him like scolding hot water, then telling him to take a lap.
Kit didn't say anything or shrug away.
"I thinks it's time I gave you something." Jace said as the other blackthorns started to get up and leave, discussing lunch. All except Emma and the twins.
Jace walked over to Kit and pulled something out of his pocket. A ring.
Kit stepped back.
"If your proposing," Kit said worriedly, "you should know-"
Jace cocked an eyebrow. "You aren't gay? You don't like strong and handsome mean, with angelic features?"
Kit wondered what Will would say about this insufferable guy, who is related to them. Will has a calming presence, he's basically the human form of an ocean breeze. But he would be bothered by Jace's cockiness. He already has a hard enough time with Kit's sarcasm.
Thinking about Will made Kit's heart sink. He hasn't told Will yet. Will doesn't even know his own father is dead.
Kit swallowed and shook his head. "No- I just don't like you."
Jace looked ready to take the challenge. "All in good time, my blood spring, but today I'm just giving you the family ring. It used to belong to Lucie Herondale." In his palm was said ring, silver and bold.
It was a family ring, with the letter H incrested.
Jace put it in Kit's hand. "Plus, it can't be sold." He looked Kit in the eye. "Just saying."
Jace had caught Kit trying to steal at least four times. He was too much like their cat chapel, quiet and quick.
Kit begrudgingly took it, feeling as if he'd just taken another burn to hand. But there was also something grounding about it. Even though Kit could barley admit it to himself, he was a herondale and Jace part of his family. For a moment, Kit let onto his finger and admired it. He wondered what his father would say. What Will would say. What Chiron would say.
Oh no- don't even get Chiron started on nephilim. When Johnny had taken Will and Kit to camp half-blood, bruised and bloody from the journey there, Chiron made the twins swear by the river Styx to tell them campers nothing of the nephilim, and the nephilim nothing of the Demi-gods.
Kit's hand and heart still remember the oath, the feeling of promise.
But fate had spilt that promise in two, and now Kit had to pick a side.
Of course it would be the side of the Demi-gods. It had to be.
But the feeling of the ring itched his skin. He couldn't help but feel the pull.
Then he blamed it on the fall.
"Kit?" Ty asked, snapping Kit from his almost existential crisis.
"Huh?" Kit looked around, they seemed to be the only two in the training room now.
Ty tilted his head, not quite looking Kit in the eye. "Livvy and I are going investigating later. I want you to come."
Now that took Kit by some surprise. Ever since he got here, Ty has been wanted Kit to be a Watson to his Sherlock. Sometimes, Ty would come late and night with a witch light in hand and talk about everyone now staying at the institute.
Oh don't even get Kit started on the centurions. And Kit though the Roman centurions were bad enough- but shadow hunter centurions were the worst.
"About the centurions?" Kit asked
Ty nodded eagerly. "Yes. I saw Zara sneaking through Diana's office. I think she's trying to get some information on Diana before the-"
"Hey," Dru interrupted them, standing in the door way. She was out of training gear and in one of those horror movie shirts of hers. "Lunch is ready. Come if you don't want to starve." She left with that.
Man, Kit thought, Nico would love that kid.
Kit blinked and turned to Ty. He grinned, though he knew he shouldn't.
"Let's do it. I want to find something so dirty on Zara that her father will crinkled that stupid unibrow of his."
Ty stopped for a moment, and Kit started to panick that maybe Ty didn't understand, but then Ty smiled.
Kit felt something light in his chest expand, though he knew he shouldn't.

That night after Dinner-
(That had to be the most interesting dinner Kit had ever been too. Finally, finally, someone started back talking to centurions. Emma freaking Carstairs unleashed hell when someone called Mark a half blood with no honor. Then Julian had to hold her back, and she ended up giving him a bloody nose. He didn't even wince, he just sighed, sighed as blood rushed down his face. Of course, Emma said sorry like a thousand times, then turned back around to stab someone with that sword of hers. Dru started laughing so hard she had to leave. Cristina and Kieran- the lover of Mark's- looked ready to commit homicide. And Ty and Livvy watched everyone closely, though Ty didn't like the loud noise, so he put his headphones on. He then nodded at Kit, like they'd made progress somehow.)
Kit sat in the middle of his room. His hands were shaky and sweaty.
He was going to do it. He was going to send an iris message to Will, explaining- well....everything. He hoped Will could forgive him for not saving their father.
After he did that, he sent it away with his pulse tremoring.
What was will going to think when he got the message? Would he be disgusted with what he is? Will he want Kit to come back? Could Kit come back? He didn't know what Chiron would say if he found out what Kit and Will are. So in the message that's why he specially told Will to keep it to himself, though it was a large burden.
Kit wondered what to do now- maybe hop on a bus to New York, but he wondered if he could out run the monsters and the recently added demons.
Kit peered down at his ring finger, that reflected in the moon light pooling in from the window.
Just then a knock pulsed at the door and Ty stepped in, dressed in full gear. His silver eyes were alight with excitement.
Kit found himself liking this version of Ty better, when he had his Sherlock Holmes face on. A happy face on.
"Are you ready?" He asked quietly. "We have to go now."
Kit nodded, a smile spreading across his face, though he knew it shouldn't. Kit reached down to his belt, he was too in gear, and pulled out a witch light.
The boys made way for the window.