Inui Ichiko

Arihiko's older sister. Her nickname is Miss Strawberry.
Because Shiki has been hanging out at the Inui house since he was a middle school student, Ichiko could also be considered an acquaintance of his. Or perhaps it would be better to call her an existence he can't defy.
Though her way of life is even more self-indulgent than Arihiko's, she is a splendidly independent adult woman.
As far as Shiki and Arihiko know, she's a mysterious person who changes jobs about once a year.
Sometimes if something good happens she'll give Shiki a present to commemorate it, but invariably it's always something completely inscrutable. Still, since it seems to mean a lot to Ichiko, Shiki values them greatly.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised