Captivating Song (Su) A harpy's song has the power to infect the minds of those that hear it, calling them to the harpy's side. When a harpy sings, all creatures aside from other harpies within a 300-foot spread must succeed on a DC 16 Will saving throw or become captivated. A creature that successfully saves is not subject to the same harpy's song for 24 hours. A victim under the effects of the captivating song moves toward the harpy using the most direct means available. If the path leads them into a dangerous area such as through fire or off a cliff, that creature receives a second saving throw to end the effect before moving into peril. Captivated creatures can take no actions other than to defend themselves. A victim within 5 feet of the harpy simply stands and offers no resistance to the harpy's attacks. This effect continues for as long as the harpy sings and for 1 round thereafter. This is a sonic mind-affecting charm effect. The save DC is Charisma-based.
Usually something like this is a standard action, but then why does a victim stand and offer no resistance to the harpy's attacks if she isn't maintaining the song? Does the harpy just have one round after she stops singing to deal these un-resisted attacks?
didn't we just discuss this last week? oh yeah, here is a link to that discussion.