Hope is exactly that, in the purest sense of the word. Hope has existed ever since the conception of Existence, alongside its twin Counterpart, Despair. Hope is an optimistic feeling, a positive mindset based on a confident outcome of good expectations and desires. Given physical form by Liam, who sought to better understand his power, Hope has now taken on the appearance of  Monkey D. Luffy, who is known for his optimistic and joyful attitude. He is exploring the world, like Liam wished him to.