Midori is the mother of Kei Takishima, and they're very alike. She's always away on business trips, but cares for Kei a lot. When she meets Hikari she wants Hikari to ask a lot of things for her, so she can spoil her like a daughter. Hikari notices that she actually wants Kei to ask things from her but he never did. The chairman of the Takishima company is the father of Midori.
She is Aika's salvaging partner and her Boss' daughter. Her mother divorced after she was born. She wants to run the business better, but her father keeps to his policies. She does not like being left out of transactions nor having Aika do the work herself. Rion looks upon Aika like her real sister and yearns to become like Aika. (Source: Wikipedia)
A beautiful girl with unbelievable strength, Nagi is Kei's cousin and is a year younger than him. She appears during a brief vacation the SA take at Akira's villa, where they intend to celebrate Kei's coming birthday. Extremely arrogant and full of pride, Nagi proclaims herself to be Kei's fiancée and loves him very much. However, she quickly becomes jealous of Kei and Hikari's closeness with one another and ends up acting unpleasantly towards the rest of the SA in order to get Kei's attention. Upset that Kei, the only person she feels comfortable around, cares more about Hikari, Nagi tries to get rid of Hikari, who comes to see that Nagi only wants to please someone she cares about. Afterwards, the two reconcile and become friends. (Source: Wikipedia)
Izumi Takishima is the mother of Midori Takishima and wife of Kaname Takishima.
Kei's grandfather, Kaname Takishima, is the head of the Takishima group and is a powerful man in a business world. However, he is rarely seen by others, including his own family members. He makes his first appearance in chapter 25, when he makes a phone call to Kei's father. When Hikari speaks with him over the phone, he plants the idea in her head that Kei is burdened by her very presence. She meets him face to face in Chapter 59, when President Takishima tries to convince Hikari to transfer schools. He disapproves of Kei's relationship with Hikari and makes many attempts to separate them, such as sending Aoi, arranging marriage meetings for Hikari in London, and arranging a marriage between Kei and a girl named Alisa. The President expresses a strong dislike of Hikari and the mere sight of her sickens him. It is eventually revealed that he feels that he and Hikari share similarities that will make the people they love suffer; as a result, he fears that if Kei remains with Hikari, he will endure the same fate as his grandfather did. (Source: Wikipedia)
Leader of the four Golden Delmos. She's charged with the assassination of Aika but she fails both times. It's unclear if she survives in the last episode.