It won't touch you, but still a good movie short
Things I liked: background music (appropriate), animation, not too preachy, he actually comes from a violent world himself (what's with those aliens who live in peaceful utopias and then wind up on earth, amazed at our violence?), and you don't summarize the story too much.
However, I think the movie could be better with a few minor changes. For instance, I think you should stick to showing, rather than telling, as much as possible. You don't need to have the kid in the alley say "Thank you;" we can see it in the tears. Likewise, I think you should take out the "messed up kid" line; it doesn't add anything.
The same goes for some of the other text. When it says he witnesses all sorts of evil acts, couldn't you flip through a few still drawings of what he sees? You might add a few day-night-day light changes in that scene too. Maybe it's just me, but it's strange reading about the passage of time without seeing some sign of it.
I don't mean to nitpick, that's just how I am. Really, I thought it was very well done.