The artist has demonstrates a pretty good understanding of how to use the mediums used in this piece. Though despite that, the pose used is very odd and doesn't feel natural.
To start, at first I thought maybe Lupin was sitting but with the absence of a chair it doesn't feel like the character is sitting either. Even if the Lupin was sitting, the very positioning of the legs is a unnatural pose to be in, I tried sitting like that to see if it was possible, it is to an extent but again it is an unnatural pose that would require a person to sit on the edge of their seat to be the case. Assuming the pose wasn't a sitting position, this still proved to be an odd pose for the legs, the knee on our right looks like its out further then the leg on our left, this is where the leg positioning starts to look odd, the foot our front is drawn to be much further forward or around the same forward spot as the knee on our right. Again this makes the pose very unnatural as most humans wouldn't stand like that and even a humanoid figure most likely would not as well.
Another thing I was confused with is what part of the piece is the central focus, an out stretched hand usually becomes one of the central focuses, but because expression seen on the face, and the hand not feeling as stretched out as it could be makes the eyes wonder a little to much trying to figure out what it is the artist wants to draw the viewer's attention to.
The work itself is nice to look at but I would suggest next time for the artist to look at references of people sitting/standing or whatever it is the artist was going for as far as posing goes to avoid the unnatural feeling this pose has.