He goes to Lex's most days after school.
Usually Lex is still busy when he arrives, and they sit in his office together, Lex working, Clark doing his homework. Lex helps him if he asks, but that's been happening less and less often (either the material's getting easier, or maybe Clark's just being different again), so it's usually soft and quiet as they work.
Other times, Lex is angry, or strung-up, or just tired in a way that Clark doesn't think people should be unless they've lived a good fifty years longer than Lex has. He sends Clark away those days -- "Go home. Get out of here." -- but Clark never goes. He stays as close as he's allowed to be, which usually isn't very, but either way, he's still there and Lex knows it, and that's important.
There are days when Lex finishes his work early. Clark looks forward to those times, when Lex will stand and come and lean against his desk, cross his arms over his chest, and just look at Clark till he blushes, even now. Lex laughs then, and that's all the invitation Clark needs to go over and touch him. Lex's mouth and hands, different every time: confident, playful and amused, wanting, or something else that Clark can't even name, saying and asking for things that he knows Lex never would say out loud.
It's those afternoons that he leaves the mansion flushed and happy, but the glow fades once he gets home to his parents. Things are different now, however much they all pretend. His father slaps him on the back more often than is necessary, making bad jokes and talking with him about sports. His mother stops him as he walks through the house, puts her hands on his arms and just looks him up and down. Clark thinks he might have been hugged more times in the last few months than the rest of his teenage years combined.
When they think he's not looking, his dad looks confused, like he doesn't quite recognize Clark anymore, like maybe he's wondering what happened to his son.
His mom just looks sad. Resigned.
If he were younger, there would be rules and lectures and warnings and arguments. It wouldn't be like this, with them treating him like a skittish animal, with the three of them tiptoeing around the subject like something's going to shatter. But Clark's eighteen now, and his parents look at him like they're memorizing him for when he leaves.
And the thing is, they're probably right. Clark loves his parents, and he wouldn't even do anything to hurt them, but if he had to choose....
His parents have each other, and they've had Clark for fifteen years. They could get along.
Lex needs him. Lex doesn't have anybody else: everybody he did have died, left him, and if Clark did, too, that would just be the last piece of confirmation Lex needs from the universe. Lex has been waiting for him to leave; Clark's figured out that the reason he doesn't bring certain topics up (his parents, Lana, his future) is because he's certain he's going to lose.
This is the only way Clark can prove something to Lex, show him what he needs him to know.
So almost every afternoon, Clark goes to Lex's and tries to tell him he's going to win, and goes home and pretends nobody's going to lose.
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