What is the name of the ghost who haunts the Hogwarts library?
The Grey Lady, also known as Helena Ravenclaw
<s>[INST] <<SYS>> Answer as briefly as you can to the following question. You are required to give a one-shot answer: <</SYS>> What is the name of the ghost who haunts the Hogwarts library? [/INST] The Grey Lady, also known as Helena Ravenclaw </s>