She didn't know how many hours she spent in his kitchen trying to use some guy named Pythagoras' theorem to figure out some strange angle. Long enough for Paj to start asking where she went every day, since she wasn't hanging out in the garage now. Long enough to know that, on Tuesdays and Thursdays, he had a boy named Stephen who came to learn algebra, and on Wednesdays it was a girl named Christine who needed help with Trig-who Cat thought looked like one of those kewpie dolls you win at a county fair. On Mondays and Fridays, thought, David was all hers.

On those days, after the books were thankfully closed, she would linger as long as she could, eyeing his shelves, picking up his trinkets. He seemed to be collecting more of them, odd things, small statues, strange metal objects, and she liked exploring his house, her fingertips brushing the perimeters, as if testing the boundaries every time she came. And he always watched her. He would sit quietly in the large black easy chair, or on the soft leather sofa, and just watch her wander around the room. He looked casual, his arm across the chair or sofa back, his leg crossed the way guys do, his ankle resting on a knee, but his eyes were like beams that followed her wherever she went.

And they would talk. In fact, she tried to keep talking, or keep him talking, just so the time would pass, hoping he wouldn't notice her lingering. She told him about her mother and stepfather and the pressure of getting ready for college.

She told him about Stuie, and Paj, and even hesitantly revealed her dream of becoming a race car driver. She had expected him to laugh, like everyone else did, but he hadn't. He'd just nodded appreciatively and probed a little more. She loved him for that.

And then she hated him. That was a Friday, and she stayed quite late, until it was actually growing dark. The doorbell rang and their eyes met quickly, furtively, as if they had been caught doing something secret. David made some comment, she couldn't hear what, but it was a woman-a very tall, very blonde, very beautiful woman-at the door. He had apparently forgotten he had a date-