It's considered to be a good Pokémon for beginners because of its friendliness, but its disposition grows rougher as it grows up.
This Pokémon has lived with people since times long ago. It can sense when its Trainer is in the dumps and will stick close by its Trainer's side.
As they develop, their disposition grows more violent and aggressive. Many Trainers find them too much to handle and abandon them.
When it rubs the rocks on its neck against you, that's proof of its love for you. However, the rocks are sharp, so the gesture is quite painful!