Sakuya Mori has Dissociative Identity Disorder. An uncommon and extremely rare mental illness that is better known as a "split" personality. Though his "other" self has been hibernating for the better part of his life, the overwhelming stress and tiring cycle of his work has caused his counterpart, Haruka, to reemerge after 20 years of inactivity. Haruka's a free spirit that knows what she wants and how to get it. However, Sakuya doesn't even know she exists.