Spike is a very young and impressionable purple scaled yellow belled dragon. A lot of things have happened in his day to day life. He's gone through a lot of events and spells that have changed his view of this once child like world that he had set in his mind. He's come to grip that this world is pretty harsh and dangerous no matter where he goes.

And yet he still can't overcome this fear of never knowing who he is or what he'll be.

Which is why he feels as if it would be better to think of himself as simply. Not Spike.