His face falls and he looks for a moment like he's been crushed underneath one of her heels. All of a sudden she feels like the worst person in the world, but this really isn't how she expected this to go. There are probably a thousand better ways to handle it, plenty of girls who would be over the moon if this happened on their anniversary, but Isabelle isn't one of them.

"Just--" she makes an impatient gesture for him to stand up, desperate for him to get off his knee. At least then she can look him in the eye while she tries to explain. "I'm not exactly wife material, Billy," she says after a moment, frowning. She's a Shadowhunter and that's always going to come first. She thinks he understands that, even, so maybe that's not an obstacle the same way she sees it. Or maybe she's got this completely wrong, but now that she's started she feels like she has to see it through to make sure they're on the same page.

"This is all really sweet and I'm sure if I was anybody else this would be perfect, but it's just not me." Not now, anyway. She doesn't want to say she's ruling it out for all eternity, but it's not something she ever really saw on the cards.