Gavin choked and his face turned the most adorable shade of pink. He glanced around the trolley car, but it was still early and so mostly empty. I doubted the elderly gentleman in the front of the car or the overdressed family in the back were paying any attention to us. "s*x," I said, "You and Kelly did it, right? What was it like?" "I don't know if I should be talking about this with you," Gavin said. I couldn't tell if he meant the sibling thing, or the chastity thing, or just the couples' privacy thing. Probably all three. "Lilah gave up her purity ring," I said, "She met some guy at camp, and I guess they, I don't know. It got me thinking, that's all." "Oh, that makes sense," Gavin said, "Look, just because your friend broke her promise doesn't mean yours is any less important. It

