The Binding

Using these hearts, cast a spell at the summoning circle to open a doorway for the succubus to come through. Your powers are greater now, and you will need all of them to defeat the succubus.

Beware its charms, <name>, many a strong mind has been bound to its will. When overcome, the succubus will be returned to the void, and I will teach you the spell to summon it forth at your command.