As the title suggests he's a vampiric dragon i.e. a dracyre. They're slightly more common than dracoliches and are equally despised by normal dragons for being an aberration to the species.
Azeth features early on in the Daemonslayers and gets a mention in 'Heritage' ... he was the creature that moved into Uth Nagor during Bloodbane's 'absence' and Shade and Blackjack (with a little help - it's also the story where Raven first shows up) have to get the unwelcome squatter to move on.
Those fangs there flick forward when he bares his teeth to strike, otherwise they are swept back against the outside of his upper jaw.