The graduation ceremony itself, beside being the fairly boring rite of passage that it naturally was, also marked the apex of the siblings' day of suppressed desires and surreptitious pleasures. In the middle of the valedictorian's speech, while they stood side by side on stage among their classmates in front of an auditorium crowded with parents and relatives, Michelle lightly elbowed Tyler, just enough to call his attention and have him lean closer to her. As his sister whispered into his ear in a giggly tone that she had just rubbed one off right there with her hand hidden underneath her graduation gown, Tyler let out a grudging sigh and...