Saki Kasukabe (春日部 咲)

She is Kousaka's girlfriend. Fashionable, violent, confident, occasional smoker, and not at all attracted by the sexual charms of anime characters, Saki is not an otaku in any sense of the word. She follows Kousaka into Genshiken, and is eventually blackmailed by the first Genshiken chairman into joining the club. Surprisingly, Saki actually saves Genshiken from being shut down on two separate occasions, though her motives have more to do with revenge and guilt than becoming more of an otaku.

Despite being vehemently against otaku activities such as wearing nekomimi (cat-ears) at the start of the series, Saki eventually becomes comfortable with the other club members to the point that she can be considered their close friend (aside from the possible exception of Kuchiki). Saki has a tendency to use nicknames. She calls Sasahara "Sasayan," Kugayama "Kugapii," and Ogiue "Ogichin" by nicknames, and even though she at first refuses to call Kuchiki by his self-appointed nickname ("Kucchi"), Saki starts using that nickname as well.

(Source: Wikipedia)