银河帝国的门阀贵族社会的腐败,以及在自由行星同盟中被称为“民主主义的弊端”的群愚政治正侵蚀着两个国家。之后,宇宙历8世纪末,两位天才的登场驱动了历史。“常胜的天才”莱因哈特·冯·罗严克拉姆,以及人称“不败的魔术师”的杨威利。两人率领着帝国军与同盟军,展开了不知道是第几次的冲突。
Sue, Cheryl, and Lexi are best friends. They do special things on their birthdays every year because they were all born on the same day. It's their 18th birthday now, and they're starting to lose their virginity.
女主(久间田琳加 饰)的高中前男友成濑大和(盐野瑛久 饰),同时也是男主(山中柔太朗 饰)的哥哥,三人将展开一段复杂的三角恋爱。