What is Lous' dream?

To play his instrument in a band without having people be afraid of him.

he wanted to play música without anyone being scared of him

Originally, he thought that part of his dream was to become human.

But he only wanted to be human because he didn't want to be feared. When Tiana and Naveen found a way for him to perform in a jazz band without everyone running away screaming, he was happy.

Really, his dream is to play in a jazz band. The drawback was that everyone was scared of him!

His dream was to perform jazz on his trumpet in a band without people being afraid.