Not necessarily the exact scenario. Basically, you are relatively young and unattached, and some 90 year old billionaire or billlionairess wants to marry you. The man or woman is a decent person who wants a younger person to spend their final years with. You have an ironclad prenup drawn up guaranteeing that you will not be ripped off in the will and cannot be disposed of by divorce - IOW you get a cool $50-100M after the spouse’s lifetime runs out. All you have to do is be a loving spouse for this person who is three times your age. Do you do it? I think I would.
I should add that the hypothesis assumes no deception involved - you are not convincing the guy that you would do it even were he not rich. It is understood that you think the person is a decent person whom you might marry were it not for the extreme age difference, and that money is overcoming that particular objection.
Absofrickinglutely!!!
I sure would.
The only thing that would concern me is that these old ladies who are very wealthy can afford superb health care, and consequently they live to be 110. It could be a long wait.
But it would still be worth it!
This reminds me of the story, purportedly about Winston Churchill and a lady at a party:
Sir Winston: Madam, would you sleep with me for a million pounds?
The Lady: Why, I guess that I would.
Sir Winston: How about one?
The Lady: Well I never! What kind of a lady do you take me for?
Sir Winston: I thought that we’d agreed on that; now we’re just haggling on price.
No. Absolutely not.
what ShibbOleth said.
Unless I was the elderly billionaire. 
I’m with Shibb and DTT. How is this different from prostitution?
Possibly. Not if I loathed them though. There would have to be some genuine regard and commitment even if it was along the lines of faithful servant. I don’t feel there is anything intrinsically immoral about such a relationship although its a definite tongue-wagger (scandalous).
As long as I didn’t have to rub her feet.
hmmm…
my friends and i often discuss what we would do for 100K…not to mention 100M! 
there would have to be at least some level of attraction. if i couldn’t stand the person, then i’m not sure i could put up with it. at that point, i’m just being a ho-bag. but, if i enjoyed the person’s company and we got along, then why not.
i would like to think that money would become a secondary, bonus issue only.
but we are talking about 50-100M…now that’s not chump change.
i think a primary factor would be public opinion. everyone would assume that you’d only be there for one reason…whether that was the case or not. i think (after time) that that could wear someone down in a big-way.
of course, we are talking 50-100M…for that amount of money i think i’d be okay telling them to go F themselves as i drive into my mutli-million dollar home with a car that cost more than their home. (glad i’m not a materialistic s.o.b. 
)
so, the short answer is heck-ya. where do i signup?
How is this different from prostitution?
Um, it is the highest end of that business that I can see. You live the grand life, have one elderly client (rather than multiple people), and you are guarenteed a big ass bonus at the end of your service.
If this is selling my soul, body, mind, whatever. I will take comfort in the fact that I worked hard to make sure that old guy was happy and got what he wanted.
My life would still have plenty of good years. My family and friends can shame me all they want, but I would bet when that money is all mine they would not give me any problems when I pay bills for them.
There is just No Way someone will make this a bad deal to me. Bring on the guy that wants me to have his money, I will try my best to keep my place with him.
If I were the elderly man, and I knew some young thing was only marrying me for my money, I would make sure that she earned every bit of that money.
IfyaknowwuddImean.
As the young thing, I would probably do it, if I did really have somefeelings for the old broad.
If I married a 90 year old billionairess, I would feel an obligation to perform husbandly duties, even if I didn’t find her particularly attractive. I wouldn’t ignore my spouse like Anna Nicole did.
“Why, your nothing but a WHORE!”
“I prefer to consider myself a ‘caregiver’.”
“But they’re 3 times your age!”
“I choose to look at the situation in a more positive light.”
“By God Man! How could you possibly?”
“Because I would be thoroughly intoxicated the whole time!”
If they lived 5 years and you got 100M, thats an average of 20m/year! You Betcha! (Ya!)
Side benefit: After you collect, you become the rich dude, and can have whatever little hot toy you wanted, but for a very much longer time to enjoy it!
Damn! I have forgotten to not become drunken again!
I’d definitely do it.
How’s it different from prostitution? It’s not, really, but what’s wrong with that? It’s less humiliation than I’ve had to deal with in other jobs, and the pay is a hell of a lot better.
HOW TRUE HOW TRUE! First good chuckle of the day thanks Sublight
Come on folks, this is a cakewalk. How often could a 90-something year old possibaly want it?
Well, it’s tempting, but it morally bugs me because I believe of marriage as a fairly sacred institution.
I’d propose rather that he hire me as a companion and caregiver. I’ll stay with him and travel with him and all the rest, for a regular monthly salary. He can make it generous. Very generous. Then it’s a job. He gets what he wants, I get money I’ve earned, everyone’s happy.
This leaves the sex thing up in the air. Surely a man of 90 isn’t looking to get laid? That’s what I’d hope.
Hell yes! In a heartbeat.
I think the question is too easy.
Let’s say the 90-year-old is of the same sex as you (unless you’re gay, then let’s say that they are of the opposite sex). Would you marry them, for $50,000,000.00?
Tough call, but I’d still do it.