first of all, it's not 12, it's 72, and it's not literal, it just mean many virgins.
1. Hoor mentioned in the Qur’an
The word hoor occurs in the Qur’an in no less than four different places:
(1) In Surah Dukhan chapter 44, verse 54
"Moreover, We shall join them to companions
With beautiful, big and lustrous eyes."
(2) In Surah Al-Tur chapter 52 verse 20
"...And We shall join them to companions, with beautiful,
big and lustrous eyes."
(3) In Surah Rahman chapter 55 verse 72
"Companions restrained (as to their glances), in goodly pavilions."
(4) In Surah Al-Waqiah chapter 56 verse 22
"And (there will be) companions with beautiful, big and lustrous eyes."
2. Hoor Translated as Beautiful Maidens
Many translators of the Qur’an have translated the word hoor as ‘beautiful maidens’ especially in the Urdu translations. If hoor means ‘beautiful maidens’ or girls, then they are meant only for the men. Hence, what will the women get if they enter Paradise?
3. Meaning of Hoor
The word hoor is actually the plural of ahwar (applicable to man) and of haura (applicable to woman) and signifies a person having eyes characterized by hauar a special quality bestowed upon a good soul, male or female in paradise and it denotes the intense whiteness of the white part of the spiritual eye.
The Qur’an describes in several other verses that in paradise you will have azwaj which mean a pair or spouse or companion which means you will have spouses or companions pure and holy (mutaharratun means pure, holy).
"But give glad tidings to those who believe and work righteousness, that their portion is gardens, beneath which rivers flow. Every time they are fed with fruits therefrom, they say: "Why, this is what we were fed with before", for they are given things in similitude; and they have therein companions pure (and holy); and they abide therein (forever)".
"But those who believe and do deeds of righteousness, We shall soon admit to Gardens, with rivers flowing beneath – their eternal home; therein shall they have companions pure and holy: we shall admit them to shades, cool and ever deepening". [Al-Qur’an 4:57]
Therefore the word hoor has no specific gender. Mohammad Asad has translated the word hoor as spouse and Abdullah Yusuf Ali as companion. Therefore according to some scholars a man in paradise will have a hoor that is a beautiful maiden with beautiful big and lustrous eyes and a woman in paradise will get a man with beautiful big and lustrous eyes.
4. Women will get something exceptional in Paradise
Many scholars say that in context, the word hoor used in the Qur’an refers only to ladies since gents are addressed. A reply that would be accepted by all types of people would rather be the answer given in the Hadith when a similar question was posed that if a man gets a hoor, a beautiful Maiden in Paradise, then what will the women get? The reply was that the women will get that which the heart has not desired for, the ear hasn’t heard off and the eye hasn’t seen, indicating that even the women will get something exceptional in Paradise.