I got the idea from http://endless-spirit.deviantart.com/art/Pages-276-277-180908430
Un-pencilled sketches in ink pen (for all but the top right one including Pentel brush pen) on book pages.
The upper left one is sold, the other three available.
If I disappear, I will have been killed by a certain bibliophile mage, but since he's fictional, that's unlikely to happen.
Comments and feedback are always appreciated!