https://www.d20pfsrd.com/gamemastering/other-rules/intrigue/#EnchantmentsCharm Person: The main thing to remember about charm magic is that it is not a compulsion (that is a different subschool of enchantment), which means it doesn’t directly force someone to do something. Instead, the spell basically makes someone feel like the caster is a friend, and puts what the caster says in the best possible light. Just like in the Diplomacy section of Skills in Conflict, being someone’s friend doesn’t mean the caster gets to dictate everything they do, and even the opposed Charisma check the spell grants can only go so far; it doesn’t compel them to act exactly as the caster desires.
For instance, an evil necromancer might be willing to allow her friend to sit as her new right hand, but she won’t quit her entire life’s goal just because a friend asked, even with an opposed Charisma check. This advice applies equally as well to other charm spells (such as charm animal and charm monster).