[MunchkinMan]

The Lust Monster provides a condition that will allow for you to defeat it (getting help from a character of the opposite sex). Curse! Necrophobia says that you must Run Away, even if you could have defeated the Monster (which would include playing cards like Pollymorph Potion, Magic Lamp, or Out To Lunch). The basic statement of Curse! Necrophobia is that you can not and will not fight an Undead Monster, therefore you will always find yourself unable to win and therefore must leave immediately, regardless of whether you're helping or the main combatant.