Summary: Au Lucifer/ Shadowhunters crossover.

Lucifer is Alec's real father, Maryse never believed that the man she met on a mission for Valentine in L.A. was really the Devil, just thought he was a delusional Mundane. At least until the first time Robert thought to disipline Alec with his belt and the Devil showed up and put himself between the young boy and her husband.

From then on Alec spent his summers interning at the L.A. Institute, summers mainly spent in the company of his father and Robert's memories wiped and altered with Maryse bound to never speak Alec's parentage aloud, not even hinted at.
Mostly Alec never brought up his own parentage, there was enough about Magnus' and while Magnus' fear over his reaction was justified Alec had earned his mother's hatred for first being the child of a Crazy Mundane and then the child of the devil. It did releave that she hated him more for his father than the man he'd chosen to love.

In all his years he'd never once been tempted to make a deal with his father, never thought that something would be worth it, not even Jace or Izzy's life, but watching Magnus flutter and flit from place to thing to something else with nervous energy Alec realized that Magnus was worth anything and everything, even a deal with the Devil.

I have absolutely no Idea how to tag this.
Magnus gets his magic back Trips to Edom Crossover Also the idea of Lucifer still being awkward about children dispite raising one was funny to me.
Awkward Dad lucifer Awesome Aunt Mazikeen Weird Uncles Amenadiel and Michael Alec calls Amenadiel Mennie, Michael by Chael, Maze by Maze (For this I headcanon Alec was the first to do so), And Lucifer by Lucie, and Chloe is always Miracle because Alec can see Amenadiel's hand in her existance and Lucifer tells him about everything when he calls to check in on Alec wheile Alec is in New York.
Alec has Devil Powers eventually.

Alec had hoped that Magnus would settle after a few weeks when a few days still left him a ball of nervous energy but time had done nothing to calm Magnus, if anything it seemed to make him more flighty, more figity and at first Alec hadn't known how to help, hadn't known what to do, what could he do really?

And then he'd recieved a call.

His father and Alec realised just how long it had been since he'd checked in with the man he knew was his father. The man wasn't really much for parenthood but between him and his bodyguard they had managed to be more parental for him than his mother and her husband.

It had amused him when his father had decided to go from Club owner to Detective consultant, following after a young woman who made him vulnerable, made him mortal, a miracle. That that miracle had a child, a daughter of her own that seemed to adore his father made Alec crack up everytime Maze sent him a video of Lucifer's reactions.

So, Alec had made plans and for all that he hated to leave Magnus right now this was something better done in person and Alec knew it.

"Magnus?" Alec called as he entered the kitchen.

"Yes, Alexander?" Magnus forced a smile for Alec.

"I have to go to L. A. for a few days." Alec informed him, "I need to see my father."

Not a lie, Alec had the same issues with lying as Lucifer did, he really hated it and he wondered if it was something to do with their blood.

Magnus' body language deflated, became small and if Alec dared he might even call it scared.

"Shall I pack a bag?" Magnus asked, curious, almost hopeful.

Alec shook his head, "No, I think you should stay here, Madzie misses you and you'll be safer here."

"Alexander..." Magnus began, another argument about how Magnus was really no longer safe anywhere, not with Rey gunning for him and him without his magic. Magnus was at his weakest, his most vulnerable.

"Do you trust me, Magnus?" Alec asked as he took Magnus' face in his hands.

"Of course I do." Magnus said.

"Then trust me to come back, trust me to..." Alec stopped himself before he finished that sentence with 'fix this.'

"Okay." Magnus sighed, "I'll stay here with Caterina and Madzie and your little babysitters."

Alec grinned, he'd known that his shadowhunters weren't very subtle about checking in on Magnus when Alec was held up in meetings or at the Institute or called out.

"When do you leave?" Magnus asked.

"In the morning, Catarina is giving me a Portal to the L.A. Insitute." Alec informed him, "I'll be fine."

"You better come back." Magnus warned him.

And Alec couldn't help it, "How could I not, look what I have waiting for me."

And Magnus laughed a little but it was a sad, heart-broken thing, it broke Alec's own heart and reaffirmed that this was the right choice.

Alec left the L.A. Institute without entering the building, they weren't expecting him and Alec didn't want them to know he was even here because they would want to know why he was in L.A.

Lux was the same as it always was during the day time, people passed out where they had fallen and his Father pacing behind the bar with Maze and Linda huddled together murmuring together, he'd never personally met Linda, his father's therapist but he respected her a whole lot to have survived even a month of his father and aunt.

"Luci!" Alec grinned and enjoyed the shocked look on his father's face and Maze's delighted grin.

"Alec!" Maze threw herself at him and Alec spun her, "Long time no see, little man." She said with a punch to his shoulder as he set her on her feet again.

"Yeah, some shit went down at home." Alec told her, "I'll expand later, who is your friend?"

"This is Linda." Maze smiled a secret little smile that she usually only gave her favorite weapons.

"Linda," Alec took her offered hand, "I'm Alexander Lightwood, call me Alec."

"Hi." Linda smiled nervously, "Are you another brother or..."

"No, I'm Lucifur's son." Alec smiled reassuringly.

Linda nodded, "So, the antichrist."

"No. Alec is a Nephilim, half Angel, half human." Lucifer finally spoke, "What brings you here, come on tell me..."

Alec rolled his eyes, "That has never worked on me, remember?"

It was Lucifer's turn to roll his eyes, "If things are happening in your state then what brings you here?"

"I need to make a deal." Alec said.

The glass in Lucifer's hand dropped and shattered on the ground, "What?"

"Look, I'm old enough to do this and... I need to do thins, I can certainly find someone else willing to make a deal for me." Alec informed his father, "I'm making this deal with or without you."

Lucifer stared at Alec a moment before he nodded, "Very well, what do you desire?"

"I desire to go to Edom." Alec said and watched Maze knock the bottle of Whiskey next to her over.

"Whatever for?" Lucifer asked, curious.

"I need to yell at Asmodeus." Alec said simply.

"What did he do now?" Lucifer asked with a resigned sigh.

"He hurt my boyfriend." Alec told them and then winced as the Demon and the Devil both perked up.

"Boyfriend." They said in unison.

"I'll let you interrogate me after I bitchslap my... My uncle." Alec frowned suddenly, "Hey, Hypothetical question, if I dated a Warlock whose father is a fallen Angel is that incest?"

Lucifer frowned, "In so much as Angels are related, no. While we share Mother and Father we are not related to one another the same way as humans define relation, each of us was uniquely designed and created for our purposes by our parents. Not that it would really matter as both you and Warlocks are sterile. Hybrids cannot have children, most of those that call themselves Nephilim are far enough removed from such that they are still fertile."

"Awesome." Alec said almost sarcastically.

"A Warlock, huh?" Maze nudged him, "He new or old? The older ones are the most fun." She teased.

"After." Alec insisted as he shrugged off his pack and prepared to go to Edom.

"Now?" Lucifer asked.

"The sooner, the better." Alec shrugged as he settled his blades in their places and lifted his bow and quiver in hand.

"Very well, I shall send you to Edom, in return you will answer truthfully my questions about your boyfriend." Lucifer stated their deal's terms, holding his hand out to Alec.

"Agreed." Alec said as he fit his hand into his Father's and the world spun and shifted and burned until he stood in a desert, with nothing about but dead trees and demons flying overhead.

Alec turned and saw what could only be described as a shack and headed over to it, guessing that it was Asmodeus' lair.

"Who dares enter my home?" A voice shouted and Alec... Alec had quite expected Asmodeus to be more intimidating and frightening.

Alec supposed it was his fault, perhaps it was Maze's really, that he wasn't scared.

"You are Asmodeus? Father of Magnus Bane?" Alec asked, voice strong and unshaken.

"And who are you? Did My son send a filthy Nephilim to fight his battles?" Asmodeus sneered at Alec.

"Hardly, I'm here to collect what is his and I'll be on my way." Alec promised, "We can do this the easy way or the hard way Asmodeus, I really don't care which."

"I have nothing that belongs to Magnus Bane." Asmodeus lied.

"Do Not Lie To Me!" Alec shouted and power swept into his voice, it startled Alec a little.

And it startled Alec the way Asmodeus shrunk away from him, fearful suddenly and Alec, Alec realized that his Father's power, the ones he'd inheirted that were nearly null and moot on Earth were much more active here in Edom.

"There doesn't have to be a fight, Asmodeus." Alec said, forcing his voice soft, reaching out a hand to the Fallen Angel, waiting.

There was a pause and with a rather familiar movement of his hands there was a puddle of familiar blue magic floating above Alec's hand.

"All of it, Asmodeus." Alec demanded and the Fallen tried to make himself even smaller as the rest of Magnus' magic joined what floated freely around Alec's hand, warm familiar and trusting.

Alec settled the magic in the special bag he'd asked Catarina for and tucked it away in a pocket. Alec stared down at the cowed Fallen Angel and walked over to him, dragging a blade lightly over his coat, cutting through it but not breaking the skin as he held a familiar gaze.

"Let's make something very clear right now, Magnus Bane belongs to me, if I ever find out that you've bothered him, that you have dared to contact him without permission I will come back and I will not be nearly so pleasent or lenient." Alec slid his blade into Asmodeus' side, the wound would heal, eventually, but badly, it would pain Asmodeus for the rest of his eternity, "You might be a Prince of Edom, Asmodeus, but me, I'm the heir of Hell, and I spent most of my summers learning how to punish those that deserve it, and boy, do you deserve to be punished."

Asmodeus scrambled away from Alec in fear and Alec stared at the frightened former Angel.

"Don't come near my family, Asmodeus, if you do it will be the last thing you ever do. Consider this your only warning, there won't be any others." Alec warned him, "Now, nod if you understand."

Asmodeus nodded frantically and Alec spun on his heel and left the Fallen Angel heading back to the place he'd landed for Lucifer to collect him, his father would know when he arrived back.

"Everything alright?" Maze asked as she tucked Alec into a half hug.

"Not yet, but on their way." Alec smiled at her, "And who is this little spawn?" Alec smiled at the little girl next to Maze and crouched down to look at her in the eye.

"I'm Trixie." She said and Alec frowned, glancing up at Maze.

"Trixie is a hooker name."

Trixie giggled, "Lucifer said the same thing, he calls me Beatrice."

"Ah, much better." Alec smiled, "I'm Alexander, but friends call me Alec and any one that can make Luci act terrified is a friend."

Trixie grinned, "I like him."

"Most kids do." Alec shrugged.

Trixie took Alec's hand firmly in hers as they were led from Lux by Maze.

"How do you know Lucifer and Maze?" Trixie asked as she looked up at Alec.

"It's a secret." Alec said, stopping to crouch down again, "Can you keep a secret?"

Trixie nodded enthusiastically.

"Luci is my Father." Alec whispered in the girl's ear.

"That's awesome!" Trixie grinned.

"Yeah." Alec found himself smiling as he took the girl's hand again and followed Mazikeen into a small family diner, "It really is."

"Hey, Luci." Alec said as he sat next to his father across from a blonde woman, "You must be the Miracle." Alec offered her his hand.

"Chloe Decker." The woman said as she shook Alec's hand, "And you?"

"Alec Lightwood, Miss. Miracle." Alec smiled at her before looking at his father, "Should I expect her to stick around?"

Lucifer opened and closed his mouth as Alec helped Trixie scoot her chair in.

"Lucifer speachless, I'm impressed, Detective Dan Espinoza." A man offered his hand.

Alec grimaced, "Detective Dooch?" He asked.

The man gave a grimace of his own that was answer enough, "So, how do you know Lucifer?"

Alec grinned, "I'm his spawn."

There was a moment of silence before Alec's phone rang. Alec looked at the screen, "Excuse me, I have to take this."

Alec walked away from the table before answering, "Hey, Magnus."

'Alexander, where are you?' Magnus sounded panicked and terrified.

"I'm in L. A. Where else would I be?" Alec asked, ignoring the confused glances his father kept throwing him.

'I don't know but Clary's brother attacked the L. A. Institute and you aren't here.' Magnus informed him.

"What!?" Alec cried, he ran back to the table, grabbed his bag from under Lucifer's chair, "What happened?" Alec demanded as he dug in Lucifer's coat for his keys, "Was any one hurt?"

'No deaths yet and Cat' and Madzie are working their magic on the worst injuries. And Clary is here, but you were missing and as far as the Institute knew you weren't even here!' Magnus yelled as Alec climbed into Lucifer's car, the man climbing in the passenger seat, the others getting in cars of their own.

"I have a speaker-thing, you're aren't supposed to talk and drive." Lucifer said softly holding his hand out for Alec's phone.

"Magnus, I'm on my way, I'll explain when I get there, can you wait that long?"

'I'm going to have to.' Magnus snarled, 'But you, you are so sleeping on the couch for at least a month.'

"I understand." Alec hesitated, glancing at his father but, "I love you."

'I love you too, Alexander.' Magnus said and then hung up.

"The Boyfriend?" Lucifer asked as they sped away from the diner.

"He's... Magnus is more than that." Alec admitted.

"I certainly hope so, if you're willing to confront a Fallen Angel for him." Lucifer stared at Alec.

"I'd do anything for him, Lucifer." Alec glanced at his father, "Even rule Hell if you wanted me to."

Lucifer nodded, "Well, he must be something to convince you to come out of your closet."

"Ugh." Alec sighed.

"You've met me, nothing is off limits." Lucifer smirked.

"I know, but Magnus still thinks I don't have a clue." Alec matched Lucifer's smirk as they slid into a parking spot and Alec slammed on the brakes, parking in an instant and jumping out of the car nearly before it stopped.

"Alexander." Magnus ran to him and hugged him tightly, "I'm glad you're okay."

Magnus punched his arm, "That's for lying to me."

Alec winced, "I didn't lie."

"Your father hasn't seen you at all, Alexander!" Magnus yelled.

"Robert isn't my father, I'll explain later but what are we looking at?"

"Who are they?" Luke Garroway asked as he stared at the group behind Alec.

"Ah, they are with me." Lucifer stepped forward before Alec could stop him, and took Luke's hand. "This is Detective Decker and Detective Dooche."

"Espinoza." Alec interjected throwing a glare at Lucifer.

"Yes, I suppose, they know about the Darkworld." Lucifer smiled winningly.

"The Shadow World." Alec corrected.

"What?" Lucifer sounded affronted, "When did they change it?"

Alec was already getting a headache, he wondered how Miracle managed on a daily basis.

"Lots of aspirin." The Miracle whispered to Alec.

Alec galnced at her questioningly.

"You have the same look I get sometimes when I have to deal with Lucifer." She smiled at him.

"And you?" Luke asked.

"Luke!" Catarina shouted, "Get away from him!" And Catarina threw a ball of magic at them.

They ducked.

"What was that for?" Lucifer cried, insulted.

"He's the Devil." Catarina said, "And She's a Demon." She indicated Maze.

Lucifer looked impressed and delighted, "She can see through Angel Glamour."

"Perfect." Alec sighed, and folded his hands together and raised his eyes skyward instead of closing them.

"What are you doing?" Lucifer asked, "No, No, come on he'll spoil the party, Alexander." Lucifer actually whined.

"Shut up and be glad I'm praying to Mennie and not Cheal." Alec said without turning his eyes from the sky. (Cheal is pronounced Kale. Like Michael without the 'Mi')

"Ugh, they are both drags." Lucifer muttered as the sound of wings could be heard.

"Alexander." Amenadiel smiled at Alec, "What is it?"

"This is Catarina and Luke, could you be a good Angel and explain that Luci isn't evil while we go help." Alec smiled at one of his favorite Angels.

"For you, little fledge, perhaps." Amenadiel said, "What do I get?"

Alec rolled his eyes, "You get to meet a very lovely lady that has magic."

Amenadiel's eyes lit up, he'd always been a little facinated with Warlocks but, Warlocks tended to be wary of Angels and Nephilim, and Angels couldn't fool Warlocks into believing they were Mundane.

"If you'd follow me." Amenadiel said and offered an arm to Catarina.

"Now that that's out of the way..." Lucifer started forwards.

"Oh no!" Alec grabbed the man's suit and pulled him back, "You are going to stay out here with Beatrice."

"What... But that is boring." Lucifer whined.

"Sit, Stay, good Devil." Alec couldn't help himself and ignored the choking noise from Magnus and the laughter from the others, "Now, Miss, Beatrice, you're in charge of him, don't let him wander off."

Alec stared at the little girl as she saluted him and then warpped her arms and legs tightly around Lucifer's legs much to the man's horror.

"Good girl." Alec patted her head and followed the others into the building.

It was bad, they had been lucky that Johnathan hadn't been fully recovered and Clary had been able to get away and warn at least some of the Nephilim.

"Alec!" A small voice cried.

"Max!" Alec responded and hugged the boy and welcomed Madzie into it when she come over too.

"Alec, where were you?" Jace asked, "I couldn't even reach you through our bond."

Alec accepted the hug, "Later." He said.

"Alec." His mother and her ex- husband frowned at him, "Where have you been?"

"I had to see someone." Alec said, vaguely.

"Who? Who was so important that you were unreachable?!" Maryse yelled at him.

Alec narrowed hie eyes at her and spoke coldly, "Don't yell at me like that, Maryse."

There was a pause and Alec saw his mother's eyes widen in shock.

"I am your mother..." She started.

And suddenly Alec was done with her, done with many of the Shadowhunters that stared at him like he was a freak, that mocked him and sneered at him and muttered behind his back and he was certainly tired of Lorenzo Rey who was coming over to them, no doubt to try to blame Magnus for this as well.

"You are the mortal that birthed me." Alec snapped, voice cold as ice and filled with the power that he'd unlocked in Edom to put the fear of Actual Hell into Asmodeus, "And I am done. Done with you, done with the Clave, done with foolish and arrogent Warlocks," Alec's eyes locked with Rey's and Alec didn't know that his eyes were burning with the Fires of Hell, like his father's sometimes did, "And I and done with stupid Nephilim."

"Alexander." A sharp voice echoed in the sudden stillness.

The Devil approached, Miracle on one side and Angel on the other, and hand settled on Alec's shoulder, "Let go, there is no need to punish these people now, they will get their full punishments when their end comes. Let it go."

Alec's burning eyes locked with Lucifer's own burning orbs and he did as he was told.

"There you go, just let it sink in to the Earth, she will take care of it, relax, there you are, fuzzie fluff." Lucifer murmured as he pulled Alec into his arms, combing his fingers through Alec's hair.

Alec snorted, "I haven't had fluff for years."

"No, I suppose you've grown into your own." Lucifer nodded, "Feel better."

Alec pulled away, "What happened?"

Lucifer sighed, "I shouldn't have let you go, you've, well, Awakened, for lack of a better term, you'll be coming in to the inheritence you got from me."

There were sharp gasps and Alec looked over in time to see Rey and Robert piss themselves but his eyes landed on Magnus.

The was a pause before, "You don't care about my father, I don't care about yours." Magnus said softly reaching out to Alec who fled Lucifer's arms for Magnus'.

"Speaking of Fathers." Alec pulled back and pulled out the bag of Magnus' magic, which was glowing softly and leaking Glitter of all things.

"What is this?" Magnus asked as he took the offered bag.

"What I needed to do." Alec explained deciding to ignore every one but Magnus, "It's... it's your magic. I went to Edom to get it back for you."

"You what?!" Magnus yelled, echoed by Jace and Izzy.

"You've been miserable and I couldn't stand it, Magnus, not when I could do something about it." Alec said, wanting Magnus to understand.

"Alexander." Magnus whispered.

"I um... may have also told him not to talk to you if he wanted to live." Alec expanded sheepishly.

"Alexander." Magnus said exasperated.

"I'm sorry, I think I started 'Awakening' or whatever, I felt really possessive and protective and I didn't want him to have the chance of hurting you again." Alec explained.

"Alright, I think that's all that can be done here." The Miracle said.

"Right." Several other voices echoed and Magnus reached his hand into the bag and his magic sunk into him instantly and Alec steadied Magnus when he wobbled at the rush having his magic back gave him.

"Shall we?" Magnus asked, offering and arm to Alec.

"Nope." Amenadiel grabbed both of their arms, "I'm taking you both to Lux, Alexander has training for his awakening abilities and you, Mister Warlock, have some questions to answer about your intentions with my nephew."

And then they were gone, leaving the others to follow the Detectives and Lucifer, Madzie, Max, and Catarina deciding to tag along.

It would be a while before they returned to New York but when they did they would be ready for Johnathan and anything he had waiting for them.

But Magnus had his magic back and Alec still had Magnus even if his father frightened the Warlock a little but the two had bonded over drinks and Maze and Izzy had bonded over weapons and fighting and Linda had latched onto Jace and even managed to start him talking and Amenadiel had let Madzie climb onto his shoulders and she'd fallen asleep there as the Angel spoke to Catarina. Clary and Simon finding some common ground with Chloe and Dan and playing with Max and Trixie and Alec let himself relax.

His family was finally one and he was content and they would be strong enough to face Johnathan and the Clave and anything that was thrown at them, Alec would make sure of it, he wasn't going to lose this, he wasn't going to lose his family, not for anything.

A/N: So... I have no excuse, absolutely none.

I just, when crossed over Lucifer is always on Magnus' side and I get it but on Lucifer he's not really an actual Demon but just a Fallen Angel, he still has powers and wings and that's more than Amenadiel has when he falls so I say that Lucifer still classifies as an Angel where the rest of the Fallen don't not really but Alec only hears Lucifer call them Fallen Angels and I feel in this story Lucifer's parenting had more influence on Alec than Maryse's since he actually cared even if the time spent together was shorter.

I also say that Alec spent summers in L.A. But that was more of a pick up/ Drop off place than anything else since that's where he met Maryse, Alec spent some time in Hell with Lucifer learning Punishment from him and Maze before Lucifer decided to vacation, Alec was a small factor since once he turned eighteen it would be harder to get him to Hell without killing him, and Alec didn't deserve Hell even if he did die.

So I decided to make Alec Lucifer's son. I know that there are things that may imply that Lucifer can't father children or what ever if so than ignore that or pretend that whatever remainder of Lucifer's Angel power felt Maryse's own and created Alec.