Muslims are very quick to point out the concept of Mahr(Dowry) when they talk about Women rights. If you read from Quran and Hadiths, this money / gift is basically given by husband to have SEXUAL INTERCOURSE with his wife.
4:24 (Also prohibited are) the women already bound in marriage, except the bondwomen you come to own. It has been written by Allah for you. All (women), except these, have been permitted for you to seek (to marry) through your wealth, binding yourself, (in marriage) and not only for lust. So, to those of them whose company you have enjoyed, give their dues (dower) as obligated. There is no sin on you in what you mutually agree upon after the (initial) agreement. Surely, Allah is All-Knowing, All-Wise. [Translation of Mufti Taqi Usmani]
If you read the verse above it clearly states whose company you have enjoyed, give their dues as obligated. Isn’t it similar to what a man will give to a prostitute after enjoying her company ?
Tafsir Ibn Kathir
(provided you seek them (with a dowry) from your property, desiring chastity, not fornication,) meaning, you are allowed to use your money to marry up to four wives and for (the purchase of) as many female slaves as you like, all through legal means,((desiring) chastity, not fornication.) Allah’s statement,
(So with those among them whom you have enjoyed, give them their required due,) means, to enjoy them sexually, surrender to them their rightful dowry as compensation. In other Ayat, Allah said,
(And how could you take it (back) while you have gone in unto each other),
(So, whoever of them you have benefited from, give them their due as obligated): ‘Benefiting’ in this verse refers to coition and it means that the payment of full dower is due on the husband only when he had benefited from her company by having sex with her. If, after the initial marriage contract the wife has not come to live with the husband who thus does not get the opportunity to ‘benefit’ from her company, and he divorces her before having that opportunity, the payment of mahr (dower) due against him becomes half. Special attention has been drawn in this verse to the situation when, once this ‘benefit’ has been received from some woman, the payment of her mahr becomes obligatory on all counts.
And, forbidden to you are, wedded women, those with spouses, that you should marry them before they have left their spouses, be they Muslim free women or not; save what your right hands own, of captured [slave] girls, whom you may have sexual intercourse with, even if they should have spouses among the enemy camp, but only after they have been absolved of the possibility of pregnancy [after the completion of one menstrual cycle]; this is what God has prescribed for you (kitāba is in the accusative because it is the verbal noun). Lawful for you (read passive wa-uhilla, or active wa-ahalla), beyond all that, that is, except what He has forbidden you of women, is that you seek, women, using your wealth, by way of a dowry or a price, in wedlock and not, fornicating, in illicitly. Such wives as you enjoy thereby, and have had sexual intercourse with, give them their wages, the dowries that you have assigned them, as an obligation; you are not at fault in agreeing together, you and they, after the obligation, is waived, decreased or increased. God is ever Knowing, of His creatures, Wise, in what He has ordained for them.
Tafsir Ibn Abbas
(And all married women (are forbidden unto you save those (captives) whom your right hands possess) of captives, even if they have husbands in the Abode of War, after ascertaining that they are not pregnant, by waiting for the lapse of one period of menstruation. (It is a decree of Allah for you) that which I have mentioned to you is unlawful in Allah’s Book. (Lawful unto you are all beyond those mentioned) as unlawful, (so that ye seek them) marry (with your wealth) up to four wives; it is also said that this means: so that you buy with your wealth captives; and it is also said that this means: so that you should seek with your money marrying women for an agreed period of time (zawaj al-mut’ah) but the lawfulness of this practice was later abrogated, (in honest wedlock) He says: be with them as legitimate husbands, (not debauchery) not indulging in adultery without having a proper marriage. (And those of whom) after marriage (ye seek content) from whom you derive benefit, (give unto them their portions) give to them their full dowry (as a duty) as an obligation upon you from Allah to give the dowry in full. (And there is no sin for you) there is no harm for you (in what ye do by mutual agreement) in increasing or decreasing the amount of the dowry by mutual agreement (after the duty hath been done) after the first obligation to which you have aspired. (Lo! Allah is ever Knower) in relation to making lawful to you marriage for an agreed, limited period of time, (Wise) in later making this practice unlawful; it is also said that this means: Allah is ever Knower of your compulsion for marriage for an agreed, limited period of time, Wise in making such marriage unlawful.
Al Quraishi Tafsir
And wedded women, save what your right hands own, this is what God has prescribed for you. Lawful for you beyond all that is that you seek using your wealth, in wedlock and not in illicitly. Such wives as you enjoy thereby, give them their wages as an obligation; you are not at fault in agreeing together, after the obligation. God is ever Knowing,Wise.
When you stay mindful of the limits, respect agreements and obtain mutual consent with women according to the law, there will be no enmity in it for people and no punishment to follow from it from the Real (s), for that is lawful and without further restriction.
Sahih Bukhari Volume 7, Book 63, Number 262
Narrated Ibn ‘Umar:
The Prophet said to those who were involved in a case of Lian, “Your accounts are with Allah. One of you two is a liar. You (husband) have right on her (wife).” The husband said, “My money, O Allah’s Apostle!” The Prophet said, “You are not entitled to take back any money. If you have told the truth, the mahr that you paid, was for having sexual relations with her lawfully; and if you are a liar, then you are less entitled to get it back.”
Sahih Bukhari Volume 7, Book 63, Number 261
Narrated Said bin Jubair:
I said to Ibn ‘Umar, “If a man accuses his wife of illegal sexual intercourse (what is the judgment)?” He said, “Allah’s Prophet separated the couple of Bani ‘Ajlan (when the husband accused his wife for an illegal sexual intercourse). The Prophet said, ‘Allah knows that one of you two IS a liar; so will one of you repent?’ But they refused. He then again said, ‘Allah knows that one of you two is a liar; so will one of you repent?’ But they refused, whereupon he separated them by divorce.” Aiyub (a sub-narrator) said: ‘Amr bin Dinar said to me, “In the narration there is something which I do not see you mentioning, i.e. the husband said, “What about my money (Mahr)?‘ The Prophet said, “You are not entitled to take back money, for if you told the truth you have already entered upon her and if you are a liar then you are less entitled to take it back.
Sunan Abu Dawood , Kitab Al-Nikah #2078
Narrated Aisha, Ummul Mu’minin: The Apostle of Allah (peace_be_upon_him) said: The marriage of a woman who marries without the consent of her guardians is void. (He said these words) three times. If there is cohabitation, she gets her dower for the intercourse her husband has had . If there is a dispute, the sultan (man in authority) is the guardian of one who has none.
Sunan Abu Dawood , Kitab Al-Nikah #2121
Narrated A man from the Companion of the Prophet: Muhammad ibn AbdurRahman ibn Thawban reported on the authority of a man from the Companions of the Prophet (peace_be_upon_him): When Ali married Fatimah, daughter of the Apostle of Allah (peace_be_upon_him), he intended to have intercourse with her. The Apostle of Allah (peace_be_upon_him) prohibited him to do so until he gave her something. Ali said: I have nothing with me, Apostle of Allah. The Prophet (peace_be_upon_him) said: Give her your coat of mail. So he gave her his coat of mail, and then cohabited with her.
Sunan Abu Dawood , Kitab Al-Nikah #2126
Narrated Basrah: A man from the Ansar called Basrah said: I married a virgin woman in her veil. When I entered upon her, I found her pregnant. (I mentioned this to the Prophet). The Prophet (peace_be_upon_him) said: she will get the dower, for you made her vagina lawful for you. The child will be your slave. When she has begotten (a child), flog her (according to the version of al-Hasan). The version of Ibn AbusSari has: You people, flog her, or said: inflict hard punishment on him.
Sunan Abu Dawood , Kitab Al-Talaq #2228
Narrated Aisha, Ummul Mu’minin: Barirah was emancipated, and she was the wife of Mughith, a slave of Aal AbuAhmad. The Apostle of Allah (peace_be_upon_him) gave her choice, and said to her: if he has intercourse with you , then there is no choice for you.
In our view the man who rapes a woman, whether she is a virgin or not, if she is a free woman he must pay a dowry like that of her peers, and if she is a slave he must pay whatever has been detracted from her value. The punishment is to be carried out on the rapist and there is no punishment for the woman who has been raped, whatever the case.