What is the name of the three-headed dog guarding the trapdoor in Harry Potter and the Sorcerer's Stone?
Fluffy
<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 three-headed dog guarding the trapdoor in Harry Potter and the Sorcerer's Stone? [/INST] Fluffy </s>