Takes place during CoA. There was a six word drabble a thon on Pandemonium Club on LJ and I wrote one about J/I/C and decided to elaborate. So here it is!

She's never seen his eyes so cold.

She's seen him mad at her before, seen him yell and tear his hair out in frustration, but she's never seen his eyes so cold, never seen him so frozen towards her, and she wants him to yell and scream and tear out his hair because she knows how to deal with that Jace. But this Jace scares her, because this Jace doesn't care.

"What did you think was going to happen? You knew we had no future."

"You overestimate my intelligence, Jace."

"Nothing can happen."

"It's already happened! It's already been done, Jace, would you like me to name the places? The-"

"ISABELLE!" He shouts, and she smirks, because he's yelling and he's feeling and she's winning this one, she knows it.

"It's over. I mean it."

"Of course you do, Jace. You always do." She walks over and places a hand on his arm, runs it down to his wrist, reaches up to kiss him-

He jerks away. His eyes are cold again.

And suddenly she understands.

"It's her, isn't it?"

His silence is the only answer she needs.

"What the fuck, Jace?" He's still cold, still indifferent, and she wants so badly to make him show emotion.

"She's your sister, Jace!" She screams, and she gets the reaction she wants because he snaps and grabs her arm and shouts,

"So are you! And you're more of a sister than Clary will ever be!"

"You're going to stand there, her blood running through your veins, and tell me that? You're going to stand there, knowing you have the same parents, and tell me that you think it's gross to kiss me because you've grown up with me, but that it's fine to suck on her face, even though you two are related?" His hand is steadily growing tighter on her arm, but she doesn't care. "You're going to stand there-"

"Shut up Isabelle!" He growls, squeezing tightly, and she lets out a whimper to make him think he's hurting her, inwardly smirking as he lets her go as if he has been burned, his face horrified.

"God… Izzy, I'm sorry."

But it doesn't matter that he's sorry, because he's only sorry that he hurt his sister, and she'd rather he push her down and kiss her hard than have him sorry he hurt his sister.

"It doesn't matter, Jace."

She turns away, but he grabs her again, lightly, his fingers barely there.

"Look at me, Isabelle," he whispers, and she can just picture those golden eyes burning in desire for someone else, and she remembers when they used to burn for her (but maybe that was just a false alarm).

"No," is all she says, eyes burning a hole in the wall, "all you ever see is her."