Anna is one of the twin sisters in the mutant family from the horror manga *Kichikujima (Freak Island)*. She lives with her family on an abandoned island, participating in cannibalistic rituals and cult practices centered on supernatural powers and worship of the deity Zanta Maria.

In the spin-off anime *Kaoru no Taisetsu na Mono*, Anna appears in a super-deformed style. This adaptation presents her and her family in lighthearted, slice-of-life scenarios, omitting her violent traits and scythe-wielding role from the manga. Her character design retains visual elements like a mask, but she functions as a minor figure within the comedic shorts without contextual background or development.

Anna consistently appears alongside her twin sister Kanna across both the horror manga and comedic anime iterations. No additional backstory, individual character arcs, or specific narrative focus on Anna are provided.