Introvert and extravert. Introvert and extravert, basic personality types according to the theories of the 20th-century Swiss psychiatrist Carl Jung.
Charles Joseph Charlie McDermott is an American television and film actor, currently known for his role as Axl Heck on ABC's The Middle. Since 2004, he has worked on a wide range of television series, including The Office and Private Practice.
Derek Wellington. Kaitlyn's current boyfriend is Derek Wellington, a minor character. While talking with Hazel, she confides she does not think the relationship will last, due to Derek's personality, and the fact he is too much of a boy for her tastes. Later in the book, they broke up.