Aaaah, this look so nice! I love the more darker tones of this, and then you have the red feather of the pen that stands out against the background! I would keep it grey scale, it really puts focus on the dragon and the whole idea of it.

The dragon looks very awesome as well, the design of the yellow against the more lighter grey really shows off the round yellow gems(?) and those long ears? Are super cute and emotive, it looks very attentive as it scribbles down the going ons of things around~ <:

Great job!