R24/7 -Twenty Four/Seven-

"You just a sex slave for many men for the next 7 days.
Perhaps, a word 'used' would fit better.
We will provide you the basic needs for living, but you are prohibited to have any contact with outside.
You are also not expected to have a right to your basic humanity. Please be aware of that."

Game System
You live in the basement of sealed space for the next 7 days, with couple men.
For 24 hours, you can enjoy being fucked by men, or rest and eat. You can live freely as you wish. If you get tired, you eat. If you feel tired, you sleep.
You can enjoy having conversation with men, and you are sometimes allowed to go out at night.
You can go out only if you want to. You can also set a time for sleep.
However, if any man wants to use you for his ejaculation, you will need to obey his wish.
You can never resist their request.

[From DLsite English]