 Four adult novels based on the series , written by Midori Tateyama , were published by Movic between August 1998 and April 2000 . Each volume focused on one of the main heroines in the story ; volumes one through four focused on Mizuka , Akane , Misaki , and Rumi , respectively . A 143 @-@ page official fan book , which focused on Moon and One , was released by the publisher Compass in October 1998 , titled Tactics Moon & One : Kagayaku Kisetsu e Creation Image Collection . Aspect released a 95 @-@ page official fan book for the PlayStation version of One in October 1999 . 
