This is really first class animation which swims into the realm of Fantasy. Where time and reality are thrown out the window.
Animation by itself is gorgeous, thou first time viewers will most likely be confused what's going on in first couple episodes, thou it slowly makes more sense as you watch it.
This basically tale of a boy named Jing, who steals rare and very difficult things for a living, with his bird-pal (girl crazy) who can become living energy weapon of incredible power.
Each show has different theme and something to steal. As well as gorgeous music, and compelling stories of how is this guy going steal this thing...there the music. Japanese music for this show, specially beginning and ending themes are high energy and addictive to listen. Thou in the original language which to me, adds something more to it. Something you've never heard before.
If you like something different that borders on realm of fantasy and fun. Which doesn't need a scientific answer and does it in style.