Mikage has an older sister, Mitsuki, who was born 5 minutes before her. They haven't seen each other in awhile and rarely talk as their relationship is strained due to Mikage harboring a great deal of jealousy and resentment.
Mikage was hit by a car in what should have been a fatal car accident for her. Miraculously, she survived with only minor breaks and a few lasting scars. However, there is more to the story than even Mikage realizes right now.
She likely suffers from one form of a dissociative disorder but it has never been clinically diagnosed.
She is a registered nurse at the NWO's private hospital, Fujiwara, but she also works part time at Yumezaki Municipal Hospital in Sumaru.
Their mothers name was Amaya Kono and she died when the girls were 3 years old. They spent the following 4 years of their lives in an orphanage until their father was located.
Her father, Daisuke Kohama, is a government official and because of this she has some influence to her name as well as being well taken care of. He is also a member of the NWO but it is kept secret whether or not he is a persona-user as well.