Daisuke Saiki
Daisuke is the nephew of Aoki and a protecter/servent of Hinoto. He is also a windcaster, but cannot create a kekkai because he is not a Seal. He is very devoted to Hinoto and wishes only to protect her even at the expense of his life.

Hokuto Sumeragi
She is Subaru's twin sister and was killed by Seishiro. Before she died, she cast a spell on Seishiro which would prevent him from killing Subaru in the same manner he killed her. If he does try to kill Subaru in this manner, Seishiro will suffer the blow instead. Hokuto is the person Kakyou is in love with.

Kyougo Monou
Kyougo is the father of Fuma and Kotori and the husband of Saya. He is the master of the Togukushi Shrine and has been protecting the holy sword since his wife's death 6 years ago.

Saya Monou
Saya is the mother of Fuma and Kotori and the wife of Kyougo. She was close friends with Kamui's mother, Tooru. She became Tooru's sacrificial double and died in Tooru's place giving birth to the first holy sword. She did this so Tooru could take care of young Kamui.

Tooru Shirou
Tooru is Kamui's mother. She left Tokyo with Kamui after Saya's death. Tooru later kills herself in a fire but before she dies, she tells Kamui to return to Tokyo because his destiny awaits him there.

Tokiko Magami
Tokiko is Tooru's younger sister and Kamui's aunt. She is Kamui's only living blood relative after Tooru's death but later on in the anime she dies giving birth to the second holy sword.