Horokawa

Horokawa (幌河) is a background character introduced in the 7th volume of Shinyaku Toaru Majutsu no Index. She is a probably a member of fencing club in a high-class girl's school in the School Garden.

Agitate Halation Arc
During the wild goose chase Kamijou Touma is put in the School Garden, the girl is part of a team hunting him down. There information about Touma is apparently widely varying as they are unsure what he looks like, Horokawa even believes he is a monster like a white alligator, after deeming that Touma is underground instead of above them on a rooftop after they tracked his cellphone signal.

Horokawa's senpai suggests to her that what they're doing is not practice and that they should their sabres.

Quotes

 * (To her senpai, from NT 7): "But if this mysterious being can move freely within the sewer, does that mean he is a monster similar to a white alligator?"