Lex hates being in love. It makes him crazy, makes him want to do impulsive things. It makes him weak, distracts him, smears all the lines that he's drawn so carefully. Being in love makes him angry and hurtful, prone to lashing out, like something cornered and wounded. All the previous times he's loved he's only gotten hurt, and he has no reason to believe this will be anything different. Clark is beautiful, but he's young, and when Lex was his age he was only there until he was gone.

Clark, of course, thinks it's forever. He doesn't say as much, but he acts like it, giving Lex his all. Lex is afraid to give his everything; if he does that, then he won't have anything left for himself. He's not like Clark, who has the easy confidence and self-assurance of youth, whose cup runneth over with love.

The first time there's no sex, just making out in the loft, necking like two teenagers on the couch. Lex runs his hands up under Clark's shirt, brushing his thumb over Clark's nipples, and Clark makes a joyful, hungry sound and tries to climb into Lex's skin through his mouth. Lex has to pull back and show Clark how to slow down and be gentle, how to savor the anticipation. Clark proves a most apt pupil.

Lex makes a mental wager with himself. Six months. If this lasts more than six months, he'll be very surprised.

After six months to the day, Clark shows up with a bouquet of wildflowers and a small, neatly-wrapped present. Lex can tell it's a CD from the weight and shape of it, and he tears open the paper to find the latest Aphex Twin album. He already has it, but he's touched nonetheless, and apologizes to Clark for not getting him anything.

"No," Clark says with a shy, nervous grin at the ground, "you already give me lots of stuff. I just wanted to give you something for once."

Clark already gives Lex something, but Clark doesn't know that, so Lex takes him to bed and makes him come three times. They lie tangled together in the sheets afterwards, Clark's breathing even in sleep. Lex traces patterns in his come on Clark's chest and wonders how long this will last. He doesn't want to get too attached; he knows very well the rule about heights and falling. He thinks of Desiree and Helen and something sad and dark sits in his chest and squeezes. He doesn't want to add Clark to that list, but there's no other list to add him to.

Six months later, Lex invites Clark to Metropolis with him. They have dinner and then attend a concert, one of the popular rock bands that Clark likes so much. Lex isn't impressed, but Clark loves it, and afterwards he takes Clark backstage to meet the band. Clark gets autographs and gives shy compliments to the band members, who are politely delighted by his enthusiasm.

Lex is practically attacked in the limo.

"Don't think I don't know," Clark says, pulling down the zipper on Lex's pants and touching him with all the sureness and grace that he didn't have a year ago. "It's our one year anniversary today." He gives one of those mile-wide grins, the kind that lights up a football field, and goes down on him. Lex clutches the back of the seat and thinks that this can't possibly go on, that four weeks, four months from now Clark won't be here anymore.

For their two year anniversary, Clark shows Lex something new.

Lex doesn't usually notice too much in bed. Not in the heat of the moment, anyway; before and after he's pretty alert (a habit that develops when you never really trust the person you're in bed with). But after a few good pounds in the ass you start to lose higher brain functions, and when orgasm is close it crowds out everything else in the mind. Even Lex, though, notices when they're not actually on the bed anymore.

Clark is floating them. He has Lex's knees over his shoulders and his arms supporting Lex's back, and all Lex can do is cling to Clark while they have sex about three feet off the bed. He has no idea how Clark is doing this, what kind of leverage Clark can possibly have in midair, but he comes harder than he ever has in his entire life, stars and planets and solar systems rushing through him and crowding out his cock. When he comes to, they're on the bed again, and Clark is kissing him gently on his face, around his neck, down to his collarbone.

"Did we just--" Lex starts.

"Yeah." Clark grins, but there's a little bit of uncertainty in it. "I can fly."

Flying. Oh God, that's a world that Lex can't even begin to comprehend. Clark is a world that he can't even begin to comprehend.

"You might--you might know that I can do some other stuff."

Lex nods jerkily.

"I'm an alien," Clark whispers, and God, he sounds so young and afraid. Lex can hear him begging behind those words. Please please please please please don't hate me don't hate me don't hate me. It makes him want to laugh. Doesn't he realize? Doesn't he know?

"You're amazing," Lex says, and he means it. There is nothing about Clark that isn't marvelous and extraordinary. He stares at the ceiling and wonders about Clark's home, out there somewhere. Why is Clark here? Who are his parents? Why does Clark look so human and feel so real?

Clark buries his face in Lex's neck and breathes out slowly. Lex frees one arm and tangles his fingers in Clark's hair.

"Why are you here?" Lex wants to know.

"My planet blew up," Clark mumbles.

Lex blinks. "But why are you here?" Because Clark is amazing, breathtaking and superstrong and superfast and he can fly, and he's here in bed with Lex Luthor, who's all dark, jagged edges where Clark only radiates light.

He feels Clark raise his head, knows that Clark is looking at him, maybe with a patient, puzzled expression. Lex does not look away from the ceiling.

"What do you mean?" Clark asks.

"Why are you here? With me?" Lex has never been this honest in his life, or at least in many years. He adds that to the mental list of reasons why he hates being in love.

"Because I love you." Clark leans over and kisses him with the tenderness that comes with post-coital languor. Lex can feel himself despairing; it's too late, he's already given Clark everything of himself, and he's never known how to stop loving once he starts. But he doesn't say it; maybe then it won't be real. Clark can see it, though, and it's reflected in Clark's smile when Clark breaks the kiss and opens his eyes.

This won't last, he knows; Clark won't stay. But Lex will stop counting the years, because Clark is only here until he leaves, and Lex doesn't know when that will be.