Yes which one

Charisma
I currently possess the grace and charm of empty McDonald's food packaging

Charisma. Put it on, then use persuade to try and make him give me the other one for free since I’m on a journey to save the world.

Strength. That way, even though I'm supposed to die in the end, I can still drive off

Strength, i never cared for Carisma but I really need to clean behind the fridge.

I quicksave, kill him and take both. Then I try to wear both. If that fails I quickload and try first one then the other, loading as necessary.