Just finished this.... the idea being that an older brother is in trouble with his parents for telling his sister the Easter Bunny isn't real. As punishment, he has to take her trick-or-treating in a bunny costume. Unfortunately for him, his little sister is a bit more adventurous than he'd hoped.
I just wanted to show the process here and a share a little bit about that... I did several thumbnails of several creatures VERY quickly (look at #1 in the sketches, they were all super rough sort of like that), then when I decided that sketch was my favorite, I did three more in another few minutes, just to solidify the feelings and emotions I wanted Sherman to have.
Next, I spent about an hour on the black and white rough, and then another few hours detailing, refining shapes, and coloring.
This was something that was drilled into me at the Imaginism Studios In-House Workshop, how design and visualization before putting in too much work can make your final product that much more interesting, and also fun to paint.