The Pazuzu appears as a purple-colored monkey with bat wings and ears. He is actually a palette swap of the regular Batboon enemy. This monster is specially dangerous, since it can instantly kill all party members with its Thwack spell.
After its initial appearance Pazuzu became a regular enemy in other games in the series, such as Dragon Quest V and Dragon Quest X. It's also a recurring monster in many of the Dragon Quest Monsters spin-off games.