You could make an argument that it would still be right to take the offer, since me and frank will both die after a while anyway.
I expect I still probably wouldn’t kill frank though, since:
A: I’m not sure how to evaluate the utility of an infinite amount of time spent alone
B: I would feel like shit afterwards
C: Frank would prefer to live than die, and I would rather Frank live than die, therefore preference utilitarianism seems to be against the offer.
What if the room was already fun and you already had an infinite supply of nice food?
You could make an argument that it would still be right to take the offer, since me and frank will both die after a while anyway.
I expect I still probably wouldn’t kill frank though, since: A: I’m not sure how to evaluate the utility of an infinite amount of time spent alone B: I would feel like shit afterwards C: Frank would prefer to live than die, and I would rather Frank live than die, therefore preference utilitarianism seems to be against the offer.