We can mine this for inspiration,from the cataboligne updated in the recent Expedition to Greyhawk:
Captivating Voice (Su): A cataboligne's voice sounds like tht of a human woman. When it speaks, one designated humanoid, fey, or giant within 30 feet must succeed on a DC 22 Will save or become captivated and functions as if affected by the spell charm monster, although it remains charmed only until the demon's next action. If the cataboligne continues to speak to that victim, the effect persists (no save), but if the demon stops speaking or speaks to a different target, the victim recovers immediately from the effect. Captivating voice is a sonic, mind-affecting, language-dependent charm effect. A creature that successfully saves cannot be affected again by the same cataboligne's speech for 24 hours. The cataboligne can use its captivating voice as a free action, but can target only one creature per round. The save DC for this ability is Charisma-based.
A captivated victim walks toward the cataboligne, taking the most direct route available. If the path leads into a dangerous area (through flame, off a cliff, or the like), that creature gets a second saving throw. Captivated creatures can take no actions other than to defend themselves. (Thus, a fighter cannot run away or attack but takes no defensive penalties.) A victim within 5 feet of the cataboligne stands there and offers no resistance to the monster's attacks. A bard's countersong ability allows the captivated creature to attempt a new Will save.