So Treble over here is Tatiana's best friend (see here: http://bit.ly/tR8kec), although they work for rival agencies.
Given his wings and horns, and her wings while floating on a cloud, you can probably guess. His eyes are closed, and he is laughing with glee-- perhaps he just saw some singing on Youtube, and realizes he has been doing well at what he does!
Also given that her mission is to prevent bad music from reaching the ears of human beings, you would also be guessing correctly, if you were to presume that his job description is just the opposite.
Given the wealth of things that get professionally produced, as well as the slew of videos on the Internet that never go viral and are still a little bit chalk-on-chalkboard-esque for one's ears, perhaps little Treble actually does somehow exist!
Treble and Tatiana became best friends when she was playing in the clouds one day, stealing flat and sharp notes (which should not have been flat or sharp) out of the air so they wouldn't ever be heard by anyone. But just then, she tripped, tumbled down a few clouds, and bumped onto the cloud Treble was sitting on.
He caught her notes for her, so they didn't fall into the soundwaves. He liked her so much he gave the notes back, never telling his boss the truth as he would have been in trouble. Ever since, they've been the best of friend-- each agency kind of rolls their eyes, but puts up with it. The two kids have worked out an arrangement where she sometimes "drops" notes, and he "steals" her notes. In other words, they help each other out to where she prevents enough badly played music from being heard, and he makes sure just enough bad stuff gets through.
Again, I haven't decided if this lil' devil came into the world as is, or was a kid first-- but either way, he's just playful and a prankster. He isn't "bad," as the Westernized good vs. evil doctrines would say, and no matter whether a kid in this world is connected to his agency or to Tatiana's, they still get to play, have fun, and be involved in music-making somehow-- whether it's improving it, like Tatiana does, or making sure drek gets through, like Treble does.
I'd try to think of a different "note" to end on, but I'm falling "flat." Wow, no "score" for me on that one. I should give it a "rest," in a "major" way. The "key" is knowing when to stop...
And there I am, stopping!