Eri and Sayaka

Eri and Sayaka are friends of Shichirou Ougi who attend the same high school as him.

Personality
Eri is a fun-loving, childish and very possessive girl over Shichirou Ougi, wanting him to spend most of his time with her and Sayaka. Sayaka, on the other hand, can be fairly serious who knows that when Shichirou asks them to leave, it's because he has serious matters to attend to.

Shichirou Ougi
Eri and Sayaka appear to be Shichirou's girlfriends: he typically calls them when he wants to have fun, and temporarily forget about his problems. Eri appears to have no idea of Shichirou's other life. Sayaka, at least, knows that he is typically involved with dangerous people, and that if she and Eri fail to abide by his rules, he will stop seeing them. However, once Shichirou is informed that he will officially be recognized as clan head, he announces he will no longer have time for them.

Trivia

 * Shichirou Ougi enjoys spending time with Eri and Sayaka because they are "normal" and uninvolved with the darker aspects of his life.