Fluffy

He always did prefer the wild outdoors to being cooped up in a small room with a trapdoor. But then again, Rubeus Hagrid always did have a way of convincing him to do him favors.

Of all the people in Hogwarts, only Hagrid, and possibly Dumbledore, were respected and treated gently by Fluffy, a three-headed dog which guarded the entrance to the lair of the Sorcerer's Stone. Hagrid understood him. He knew that this dog was short-tempered and vicious with people and things he didn't want to treat nicely. But he also wanted to be well cared for, and to feel like an individual, by naming him Fluffy. Now Fluffy wasn't actually "fluffy," but Hagrid had some pleasant thoughts about him that most others wouldn't even consider.

Hagrid thought Fluffy was cute.

He liked the way that Fluffy was so big, and so natural for somebody as big as Hagrid to touch and pet and fondle. But Fluffy was also loved for his unique personalities in each of his heads. The right-paw head was "smart," always remembering what it was tasked to do, the left-paw head was "alert," being constantly on the alert for trouble and danger, and the middle head was "sleepy," always falling asleep fastest and being the last one to fully wake up.

Hagrid had always thought Fluffy was adorable for these features, as he did for other dangerous creatures, but nobody else did. Hagrid supposed that everybody else just looked at the vicious danger of the beast, and didn't stay aware that it's only an animal with a desire to be wild. They also didn't notice that Fluffy could be calmed simply by playing music, almost any kind of music; they just wanted to see him run away, leave them alone, or die.

Now, however, the Sorcerer's Stone was destroyed, and its chamber was rendered invalid. With nothing left to guard, it was time to release Fluffy. The dog's three heads barked and howled loudly as he sped to the freedom of the wild again.

Hagrid would miss him, but he knew that somehow, Fluffy would be happy with his new life. Being a guard has its rewards, but the Forbidden Forest is a much more worthy challenge for a three-headed dog.