I've never actually played DnD and don't know that much about it than I've always found the genre of sword and sorcery fantasy appealing.

This particular drawing was a "turn my brain off and draw whatever comes naturally" experiment. What it became was some kind of wizard or warlock who made a pact with some kind of entity for phenomenal magic power, but the more he calls on it the more he warps his body to the entity's twisted image.