Hm. I really like how Darius is portrayed here. A small little siyo kid with that sort of innocence and curiousity about him. His posture isn't so bad.

I like the joyed expression because it does in fact fit him. though the sorrow expression looks more like he's sighing in disappointment rather than looking down.

Although.. his hand as drawn here looks a teensy bit awkward. It's as if the bone itself is so thick, it rips out of his finger tips. Maybe it'd help if the claw tips were a bit smaller? Well at least the foot looks alright. It's the hand that needs a bit of work.

Hm, actually, the sitting pose ( the lower waist ) seems a tad off as well. May wanna work on that. It seems like the thigh, knee, and ankles are one big sausage with the foot sticking off it. Could just be me though

All and all I'd say this is a really good ref. You got everything down to tail spike. And the style you have going with it really works. Well done. Now let's see if other people actually use it.