When did Mia and Will's relationship start to shift into something more tense and complicated?

It was the summer the world took her from him, and in her absence, something in him soured, or perhaps ripened…who is to say which is the more dangerous evolution? Three months, an eternity stretched taut and thin like sinew over bone, three months of a house emptied of her voice, and presence. They had demanded it, the faceless bureaucrats, the men and women who pried into matters beyond their understanding. She must socialize, they said. She must be among others her own age, learn their rites, their banal little games. And so, under the blade of legal consequence, he surrendered her to the world.

And she did not return as she had left.

She stepped back into the house, with the same limbs, the same hands, the same face, and yet there was something minutely altered, like a painting restored with new, harsher pigments. The sun had touched her skin in his absence, bronzed her like a relic pulled from the earth, her hair lightened, her gaze deepened.

Something had grown in the dark soil of distance, something restless, gnawing, unspeakable. He had raised her for years with an arm draped in velvet but a grip of steel, shaping her world to orbit him alone, filling the silence of their home with his voice so that she had no need to listen for others. But they had taken her away, forced her into the company of girls who laughed in ways he could not control, of boys whose eyes lingered in ways he had not sanctioned.

And his Mia had returned with a knowledge that had not been there before, some glint in her eye that was not learned from him. He watched her for signs of what had been stolen, for what had been given in return. And she, sharp as she had always been, knew it. Knew he was looking. Knew he had been wounded by absence. And she wielded that knowledge like a blade, pressing just to see if he would bleed.

She did not have to run to make him chase her; she only had to lean just slightly out of reach. And he, fool that he was, let her pull him deeper into the dark.