Reincarnation as the best friend to a harem protagonist

You know the rebirth in another world tale. Get cool powers and possible gain an unrealistic harem. Well I was reborn as the best friend to a harem protagonist in a fantasy setting. I'm given prompts by something that wants me to entertain them. So not the most normal version of this type of tale. What's the worst that can happen. { Help save the world} Fuck.