Happy Ending for the Time-Limited Villainess

‘Please have a happy marriage with me only for six months’
“What good does that do me?
“We will, of course, give you the Reno family fortune and estate.”
“… Suppose you give it all to me. He said he would divorce me in half a year. If so, what do you do then? ”
“…There’s something I’m thinking about doing. I won’t be able to use this money anyway.”
Clea always lies. This body will soon die. It will only last half a year.
After a fulfilling marriage, Clea Reno wants to close her eyes for the last time in a quiet place.

When I was stabbed to death, I was summoned before the Demon King and had a six-month term as a villain.
My body uses up one energy when taking a step, three health when talking, 300 health after running for ten seconds, and I bleed when one third of my energy is exhausted.
“Oh my, she did it again to get attention.”
“It’s amazing that she takes the paint with her wherever she goes.”
“Well, Sir Detroit coldly rejected her.”
My reputation is the worst.
The demon lord said that he would save my body if I married happily, but the situation is getting worse.
I had to marry the man I was in love with, the Duke of Detroit.
I said I would do anything to get married, but I don’t know what a “happy marriage” is…
Will I be able to survive?