Bullet points about family, if notable (ie, father is a policeman, younger sister has an inferiority complex, etc).
Early childhood, elementary school, middle school, upbringing, etc.
Information about what the character was doing, if anything, during the previous year as it pertains to the war. (In the case of first years, their middle school information would go under "early years," but instances such as Tomoya watching Wataru perform when visiting Yumenosaki would go here since it more specifically pertains to the war.)
See: Appears In
Information about what the character is doing next year, if notable (ie, becomes the leader of their unit, goes on to start a company, continues being an idol with classmate A, etc).