Group:Halcyon Factory Artist:空音美樹、にゃんぞー、梶原千早 Book Info:http://www.doujinshi.org/book/1008200/FUTURE--PAST/ Artist Pixiv:https://www.pixiv.net/member_illust.php?mode=medium&illust_id=62607148 toranoana:https://www.toranoana.jp/mailorder/article/04/0030/53/56/040030535603.html