"Oh, I'm gonna bruise you. Oh, you're gonna be my bruise." – 'The Word of Your Body' by Spring Awakening
As the months go by, the transformations become easier. It doesn't seem this way at first, but by the end of the sixth transformation—half a year of the curse—Tyler feels the difference. He doesn't, however, credit it to himself and his ability to withstand the transformation any better than that first full moon six months ago. It's Caroline. It's her strength, perseverance, and sheer stubbornness to stay with him every time.
It's how she talks to him during the set up. How she holds him close as they both feel the transformation coming on. How—even thought it angers him afterward, when his head is clear and he realizes the danger—she stays with him until the last possible second before locking the gates and closing the door. And he hears her crying outside the door, hears her apologizing each time for not staying with him.
He wouldn't want her to stay, though, and he always tells her this. "I don't want to hurt you, Caroline," he'll say the next day, when both their heads are clear enough to have a real talk.
But she insists that he doesn't have a choice. "I'm not letting you do it alone," she tells him, "I'll never let you do it alone."
Afterward, when the full moon no longer controls him, Caroline rushes back in, unlocks the chains, and is by his side faster than he can follow. And she lies down on the cold stone floor in front of him, and he immediately pulls her to him, wrapping his arms around her and breathing heavily.
He no longer cries, no longer needs to—and, as she says, she does enough of it for the both of them—but he cannot help holding her a lot tighter than he should, were she still human. And he whispers half-formed sentences about her never leaving and how he could not do this without her and how he needs her. And bruises form on her shoulders, arms, waist, and wherever else his hands lock onto her body, but she tells him it doesn't matter. She always heals in the end
And then things go back to how they were, or at least, they both pretend they do. But each time they meet each others eyes, or each time they hear the others voice, they know that things cannot go back to how they were.
The effects aren't physical, and no one knows it but them, but they've both imprinted themselves onto the others heart.