Ichiko Takashima

Ichiko Takashima (高島 一子 Takashima Ichiko) is, in fact, a ghost. Her story begins 22 years ago: a previous Elder (who later became Mizuho Miyanokouji's mother) had a close relationship with an underclassmen who had a weak body. The underclassman was hospitalized but desperately wanted to see her Elder so she sneaked out of the hospital, went to the Elder's room to wait for her. Unfortunately she died before she had the chance to talk with the Elder. That room has been deemed a "closed room" ever since, until Mizuho arrived and started living in it, in accordance with his grandfather's will.

She is very energetic and hyperactive, often talking very quickly. It took some time for her to understand that she is a ghost, and by that token, dead. She notes that Mizuho looks very much like her previous Elder love interest. Although she can touch people, she cannot pick up objects and she slips through walls. Incidentally, in the anime version, she is not able to make contact with everyone. Invisible barriers initially prevent her from leaving the dorm, but she is able to leave the building as long as she's touching Mizuho in anime version, and her movable range extends to the entire school grounds after a certain event in video game.

In the video game, she has a capacity for spirit possession and it helps Mizuho's critical phase.