This is an imagined discussion between Wael and Tom. But it is based on my actual discussions.
Tom: Do you love sex?
Wael: I love sex of course. I am a human being. I have my instincts and feelings. Sex is a pleasure and sex is the way to get children. But I am Muslim. Sex is not allowed outside marriage. I am allowed to marry four women provided that I treat them equally. If I am afraid that I will not treat them equally, I must marry one woman only.
More important, in the Dayafter, we will have many amazingly beautiful wives. The Paradise is not only a spiritual Paradise, but the materialistic pleasures are innumerable there. We will enjoy delicious food, drinks, sex....etc
Tom: Why don't a woman marry four men?
Wael: If she has a child, who will be the father?
Tom: In the Paradise, a man will have many wives, but a woman will have only one husband.
Wael: A man will have the sexual power of hundred men. Thus a woman will amazingly enjoy sex.Besides, a woman will not hate other wives because in the Paradise, there is no grief, no depression, no bad feelings.
Tom: Why isn't sex allowed outside marriage?
Wael: In western countries, if you love a woman and have sex with her, you are lovers. You are not married, but if you have sex with another woman, you will be considered unfaithful. In Islam, if you have sex with a woman other than your wife, you are unfaithful and it is forbidden.