The kidnappers apprehend Mikoto in the OVA and tie her up in red string. Akira arrives and saves her from them. They are a boy and a girl who wear animal ninja masks. It gave them the illusion of being fox spirits.
Near the end, the girl addresses the male as Matsubue, lecturing him that high school kids can't drink. She thought he was drinking sake, but he claims it was just water.
It's not clear if they're actually human though, because he was able to take the cup pattern off of Mikoto's kimono and actually use it as a cup (it was just a stitched pattern). He has a familiarity with ancient things.
Muttering to himself, Matsubue refers to the girl as Togawa.