Sorry but I seem confused by the posture of the dog on the chain... Hate to be Nit Picker.

Is this a reference to Powers of 10?

Nice hommage to xkcd :)

Interesting... I've read Extra Ordinary's strips when I saw it mentioned here. I liked Li's pencil style and the strips as well :P This guest strip thing was nice too. I would like to suggest you both to switch your drawing and subject's styles and do this exercise again. I think it would be even more interesting :)