I loved his Myth Adventures stories as a kid, and was looking up a character just now on a whim when I found out the sad news. Have you read his works?
It's sad to hear he passed. Genuinely fun fantasy novels are hard to come by, but were Robert Asprin specialty. I grew up reading the Myth Adventures books, and amassed most (if not all) of the collection. Then I moved on to Phule's Company, another great series he wrote. I'm looking forward to sharing them with my son when he gets a bit older.