➰ Malec ~ Moondust (AU)

Ok, so the idea came from a simple question : What if Magnus never came to interrupt the wedding? Or, if you want to make this even angstier, what if he did show up but Alec chose his duty over him?
After the wedding that was, they start a friends with benefits kind of relationship. Alec goes over to Magnus' place and they have sex. The next morning Alec leaves and warns Magnus not to tell anyone about what happened between them.
After a while, Magnus visits Alec at the institute, where he sees Alec is injured. He gets worried, but Alec dismisses him - ah, feelings aren't allowed in their relationship, right. Instead, Alec distracts Magnus (and himself) with sex. Afterwards, Magnus leaves ("gotta go", yeah, right) and Alec watches him go. He sleeps in his bed alone...
But unfortunately, Alec falls ill and into a coma. Magnus tries to save him in any way, but it's all in vain. Eventually, he decides to ask for his father's help. "To save his life... break his heart", Asmodeus says, naming his price. So, when Alec wakes up, Magnus breaks up with him - destroys whatever kind of relationship they had.
Alec remembers his time with Magnus, slowly realizing he's in love with him. Meanwhile, Magnus also realizes his time with Alec and decides that he won't let his father get in the way. He sends Asmodeus in limbo, where he can't hurt them.
After, Magnus goes to Alec and tells him everything about the deal. Then he tells Alec he loves him. He turns around to leave, not expecting Alec to return his feelings. He only told Alec he loves him because he needed him to know that, at least. But Alec stops him, saying he loves him too. Magnus turns around, surprised and Alec hugs him. They hug in the middle of the Institute, finally together and at peace...

P.S. Check the pinned comment guys, Alec divorces Lydia after Malec says I love you. I should have probably added that in the original description. Still, it's hilarious to think Alec is married to Lydia the whole time.

Malec, at the end of the video : "I love you, Alexander!" "I love you, too!"
New Shadowhunters at the Institute, who didn't know yet that Malec were a thing, only that Alec married Lydia : "Hmm, besties with a warlock? Weird flex, but ok, Lightwood."
Another Shadowhunters : "They're gay, Steve."
Steve : "They're WHAT?"
(Steve becomes a Malec shipper after finding out the full story.)

"I'm building this house, on the moon
Like a lost, astronaut
Lookin' at you, like a star
From the place, the world forgot
And there's nothing, that I can do
Except bury my love for you

Nothing can breath, in the space
Colder than, the darkest sea
I have dreams about the days, driving through your sunset breeze
But the first thing I will do
Is bury my love for you

I'm a cast away, and men reap what they sow
And I say what I know, to be true
Yeah I'm living far away, on the face of the moon
I've buried my love to give the world to you

The brightness of the sun, will give me just enough
To bury my love, in the Moondust
I long to hear your voice, but still I make the choice
To bury my love, in the moondust"