It's hard to say without more context. She could be anyone from a friend who took over a conversation you were having about a story, to a classmate who maybe used your story idea for her own work.
According to the provided search results, there are multiple instances of individuals who have committed acts of cannibalism. In Document [1], a Ukrainian man named Sergei Lubenko was reported to have killed his girlfriend and her 10-year-old daughter, dismembered their bodies, and consumed the liver of the young girl. In Document [2], a Japanese man named Kazuyuki Sakawa was mentioned as a cannibal who killed and ate a Dutch girl in France. However, he later became a popular author in Japan. These cases demonstrate the disturbing actions of individuals who engaged in cannibalism.
I'm not entirely sure as I haven't read it specifically. But it might be a strange and perhaps fantastical story about a girl who somehow eats someone's house. It could involve elements of magic or a very unusual situation.