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The thrum of battle was almost a physical being as Jace and Alec fought back to back against the array of different demons that were launching themselves at the Shadowhunters.
"We could do this all night," Jace muttered, "Where's the warlock?"
"Magnus is looking," Alec called back.
They'd recently been investigating a rouge warlock who'd been kidnapping children to brain wash them into becoming willing offerings to his demonic father, and finally, they'd found his lair. Magnus was going after the warlock, Catarina and Izzy were helping the children and Alec and Jace were holding off the multitude of demons that seemed to be flying in from the sky.
Just then, as Alec stabbed a seraph blade through a smoke demon, he felt a hand on his shoulder. He turned, seraph blade raised.
"Lightwood," the rogue warlock said, "You. You've corrupted the High Warlock. He doesn't understand his demonic heritage because you have held him back."
"Oh wow gee," Alec rolled his eyes, "Because if it weren't for me, Magnus would've been summoning demons left right and centre."
"Maybe not," the warlock sneered, "But he'd respect his heritage a little more. He'd understand-"
"I'm sorry, buddy," Jace said, turning around as the last demons vanished into the night, "But I think it's you who needs to understand that your demon parent probably does not give a shit about you. But the Clave does. So, I'm going to have to arrest you-"
The warlock raised his hands, silver magic flowing out and throwing Jace back a few paces. Jace was back on his feet in an instant, and Alec got ready to swing his seraph blade when a blinding light of blue magic wrapped around the warlock's neck, tugging him away.
"Jethro," Magnus' voice floated in from where he was standing behind the rogue warlock, pulling him back with his magic, "Explain and account for your mistakes. I'll discuss about making your sentence shorter."
"As if I would want the mercy of the Nephilim," Jethro spat, "Just because you like to get cosy-"
Magnus twisted his fingers, pulling his magic tighter, causing Jethro to choke. His cat eyes were glowing, his warlock robes regal as he stood tall and elegant. Alec thought it was really unfair that Magnus looked like that when Alec was covered in ichor and had rips in his shirt.
"Are you actually oggling your boyfriend right now?" Jace asked, incredulous.
"Shut up," Alec thumped him on the shoulder, blushing, "Anyway. Where'd all the demons go?"
"Nice. Real smooth changing the subject there," Jace winked.
And as if on cue, the Earth seemed to shift, the air rising, the sky somehow getting darker as a tornado seemed to rise up from the sky behind the Shadowhunters.
"Alexander!" Magnus called, tying Jethro up in magical bindings before rushing over to Jace and Alec. He laid a hand on Alec's shoulder. "Are you okay?"
"Yeah," Alec said warily, eyeing up the tornado, "What on Earth is that though?"
"That may be a Portal to a Hell dimension," Magnus said, "We may be about to have a visitor."
"Do you think," Jace suggested, "That Jethro had found enough offerings to summon his dad into the world?"
"I think that's one of the smartest things you've deduced in your life, Trace," Magnus said, hands glowing as he got ready to face the threat, "Okay. Listen. If that is a demon, it's going to be powerful with all the recent sacrifices. It won't be coming on its own. It'll have its slave demons with it. Jace, go get Catarina. Tell Isabelle to protect the kids and keep an eye on Jethro. Me and Catarina will try to banish the demon back to Hell. You Shadowhunters handle the slave demons, okay?"
Alec and Jace nodded, Jace already on his way to get Catarina and Izzy. "You going to be okay, Magnus?"
"I'm perfect," Magnus said with a reassuring smile, "Especially knowing you're watching me," he winked, "I saw how you looked when I pulled Jethro back. Does me showing my powers do it for you?" he teased, "Are we going to have mind-blowing sex when we get back? Do you want me to throw you against a wall? You know, show all that power?"
"Magnus!" Alec hissed, blushing furiously "Now is not the time. And stay safe. Please."
Just then, the tornado Portal ripped open, unleashing the demons.
There was a hoard of small skittery demons that Alec shot his arrows at, each one landing true to its aim, before a larger demon materialised, red eyes glowing in a sea of black.
"Well," Magnus said, "This may be a bit more challenging than originally intended."
"Why...?"
"This is a Greater Demon," Magnus answered.
"Oh. Oh shit."
And then it was as if the battle truly begun. More and more demons fell out of the sky as the Greater Demon raised his fists, eyes glowing. Magnus shone in the darkness, his blue magic wrapping around him like vines, his golden eyes blaring and Alec realised he was also wrapped in Magnus' magic. In Magnus' protection.
"Don't stand in my way," the Greater Demon warned, "You will regret this."
"Standing in your way is kind of our jobs," Jace came into view, going to stand beside Alec, as Catarina, arms raised went to stand beside Magnus. As if on cue, a smaller demon launched itself at Jace, but he kicked it away before throwing a knife at it. And then the Greater Demon fired his first shot of demonic magic, which penetrated Magnus and Catarina's forcefield, but didn't do any harm, possibly neutralised instead. And then Magnus and Catarina fired back, magic swirling as they tried to contain the demon and open a Portal at the same time.
Alec and Jace slashed at the smaller demons, keeping them away from Magnus and Catarina, bodies moving as one as they'd always trained. If Jace kicked a demon at Alec, he knew on a instinctual level, that Alec would finish it off for him. And that relief and trust that came with fighting with a parabatai rivaled Magnus and Catarina's magic almost. This strange stalemate seemed to go on for hours until Alec heard a scream. Magnus' scream.
***
Magnus was working all his energy into holding this demon back as Catarina tried to open a Portal, fighting against the demon's magic which was leaching her powers. And then he heard, the demon's voice in his head. "Magnus Bane. I remember you being born. Asmodeous was very happy. It feels like yesterday you were just a boy. And now, you're all grown. And you're choosing the path of peace and unity and all that is wrong. A Nephilim, Magnus, really? Asmodeous is disappointed in you. You keep disappointing your family, you know? Your mother, step-father, father."
Magnus' head hurt with his own magic, with the demon's magic and it felt like he was ripping apart at the seams. His past came back to him in fitful bursts and he screamed, the anger of his childhood threatening to drown him. His loneliness, his anguish, his fragility and volatility all morphed into something disgusting, something that he had spent centuries trying to remedy, until it all broke free in a blinding light that brought the Greater Demon to his knees, allowing Catarina to pull him through the Portal. "Alec is my family." He said. Or he thought inside his head. He didn't know.
The powerful exertion made him feel out of his own body. He didn't know what he was doing. He just felt. Felt his magic roiling inside him, demanding release, felt the anger that still burned red behind his eyes, felt the fear of a young boy, one that he'd been. The hopelessness that came with having no home, no family, no love. And he turned, eyes flashing, onto Jethro, who had caused all this mess. "You," he snarled, ready to obliterate him, not even recognising his own voice.
"Magnus!" he distinctly heard Catarina call, "This isn't you! Don't do this. Come on, come on."
He barely registered her words and kept walking towards Jethro, who was cowering on the floor.
***
Alec saw Magnus throw his hands out, power errupting out of him like he'd never seen before, bringing the Greater Demon down. At that moment, he had felt so so proud to be Magnus' boyfriend. Now, he watched with panic as Magnus stalked towards Jethro and he rushed over to Catarina. "Cat, what is he doing?" He didn't recognise this Magnus, the one with blazing eyes of fury, the one who paid no heed to his friend's warning.
"He's overwhelmed with magic and his past, and - it needs a release," Cat looked defeated.
"Wait," it clicked into place for Alec, "He can't kill Jethro. He won't forgive himself. Jethro's a young warlock too. Magnus would - would want him to have a fair trial and a second chance. I can't let him kill Jethro. He won't live with it when he comes back to himself."
"Alec, don't throw yourself in there," Cat warned, "Magnus isn't himself."
Now Alec turned to Cat, eyes bright, "I know you think this is going to scare me off, but it won't. Magnus doesn't scare me. I won't let him do this."
And at the final moment, Alec rushed in between Magnus and Jethro, placing two frantic hands on each of Magnus' shoulders, searching his eyes for any trace of familiarity.
"Magnus!" Alec shouted, "Magnus, love, this isn't you. It's okay, I promise, it'll all be okay. You just- You just exerted yourself, my love. I know you're angry, but you can't do this. Come back to me. It's your Alec. Alexander. Come back to me, Magnus. I know you can. I know it's you. It's the man I love. The one who kisses me good morning even if I have to leave at ungodly hours, the one who rubs my back until I fall asleep, the one who's so caring and gentle and brave. I know you're there. Come back to me."
Alec saw Magnus' eyes flash with recognition before changing back to pure fury and back again. Magnus' hand came to lie on Alec's cheek, his magic flowing into Alec. Alec smiled, tears running down his face. "Come on, love."
And Magnus seemed to still, his eyes glazing over, until he fell into Alec's arms, with a soft whisper of "Alexander."
***
Magnus kept dreaming. Dreaming of his childhood, his father, and everything that had gone wrong in his life. Then he dreamed of Alec. Everything that had gone right in his life. All the goodness and hope and light condensed into Alexander Gideon Lightwood. Then he had fitful dreams of fighting the Greater Demon, his condescending words, Magnus' own fury, turning towards Jethro, ready to- And then Alec's panicked face, frantic as he searched Magnus' face and his voice - his voice which had stopped Magnus unleashing his powers. His blue eyes and soft voice that had brought Magnus back to himself.
Even in this half asleep, half awake state, he had a crushing realisation that when he woke up, Alec wouldn't be there. This was it. Alec saw him for what he was, and he would've left. He already saw so much more than anyone else had. Bringing him back to himself was the last favour, the last love Alec had shown Magnus. And that in itself was a dangerous, stupid decision made because Alec was just that good. Tears streamed down Magnus' face and he cried himself back into darkness.
When he finally fully woke up, he threw an arm to his side, testing where he was. He jolted when it came into contact with warm skin. Familiar warm skin. "...Xander," he croaked out.
And then he heard Alec's voice and choked on a sob. "Magnus! How are you doing, love?"
Magnus couldn't answer. He scrambled upright and realised he was in their bedroom, in the loft. Alec was there, shirtless, a book in hand, as if nothing had ever happened. As if Magnus hand't just- He threw himself at Alec, needing to make sure this was all real. Strong hands held him as he pulled at Alec frantically.
"Hey," Alec said gently, "It's okay. You're okay."
"You're still here," Magnus said.
Alec kissed the top of Magnus' head. "Of course I am. Where else would I be?"
"Alec, I could've hurt you," Magnus protested, "When you came to stop me-"
"But you didn't," Alec argued, "I knew you wouldn't. You're my Magnus."
"Alec," Magnus didn't know how to say everything he was feeling, "I'd - I'd understand if you- if you need to - I'm not - If you leave. You didn't - didn't know your boyfriend was a - a monter."
Alec tilted Magnus' face up, and said with a voice as clear as his eyes, "You are not a monster, Magnus Bane. You saved this city from a Greater Demon. The power and courage needed to do that... God, Magnus, you saved us. And even when you weren't fully yourself, you fought your way out of that. Do you know how brave that is? How difficult that is? And you still did it. You're the best person I know. I am never leaving you. I'll do whatever it takes to convince you that you won't lose me."
"Alexander-"
"If you can't trust yourself right now, trust me when I say you're not a monster. Please. You're just my Magnus."
And Magnus couldn't fight against that. Maybe he needed a few more days of being Alec's Magnus to come back to himself. But looking into determined blue eyes, Magnus realised he had someone willing to fight for him this time. He couldn't summon any words, so he kissed Alec, deep and slow, drowning in strong arms that held him as tight as Magnus pressed, needing Alec's body against him. He pushed Alec down onto the bed.
"Your Magnus," Magnus promised, "I'm sorry for everything-"
"You have nothing to be sorry about," Alec said immediately, "I love you. Not despite everything, but because of everything that you are."
"I love you, Alexander," Magnus replied and leant down and kissed Alec again before muttering against his neck, "Do you want to-"
"I always do," Alec said, running a hand down Magnus' back, "But if you want to talk more...?"
"We can talk a bit later?" Magnus offered, "I know... I need to tell you everything that happened. But I... I really want you right now. Can we? Please?"
"Already begging?" Alec teased, letting his tension go when Magnus smiled and rolled his eyes at him, "But yes, of course, we can. I was promised mind-blowing sex."
At that, Magnus coudn't help but laugh, and soon, the laugh turned into a low moan as Alec rolled them over, holding himself above Magnus as he kissed him breathless.