And yet here he was, looking at Jem Carstairs, a boy so fragile-looking that he appeared to be made out of glass, with the hardness of his expression slowly dissolving into tentative uncertainty. "You are not really dying," he said, the oddest tone to his voice, "are you?"
Jem nodded. "So they tell me."
"I am sorry," Will said.
"No", Jem said softly. He drew his jacket aside and took a knife from the belt at his waist. "Don't be ordinary like that. Don't say you're sorry. Say you'll train with me."
He held the knife to Will, hilt first. Charlotte held her breath, afraid to move. She felt as if she were watching something very important happen, though she could not have said what.
Will reached out and took the knife, his eyes never leaving Jem's face. His fingers brushed the other boy's as he took the weapon from him. It was the first time, Charlotte thought that she had ever seen him touch any other person willingly.
"I'll train with you," he said.

Cassandra Clare