Actually, I learned this term this morning. On the way to my company, I saw an advertisement of above shoujo manga, ホタルノヒカリ[hotaru no hikari “Lights of Fireflies“] on the train. This manga is currently ongoing and a live-action TV drama series of this has started. A 27-year-old working woman, Hotaru Amemiya is always respected by everybody else because of her great performance. But meanwhile, she always goofs around whenever she is off. And of course, she doesn’t have a boyfriend, so that she doesn’t have to care her looking expect her working hours. Just like her, a woman who has stopped loving anyone in her twenties…is 干物女[himono onna]. 干物[himono] means a dried fish, and 女[onna] means a woman. So in short, 干物女 means a dried woman literally. Oh dear!
If this comic got so famous, this term would be also common, I guess. And know this term does not include any definitions of otaku. So 干物女 is not otaku, nor even 腐女子[fujoshi].