exactly 72 virgins (virginity is just one of their attributes) is not in Quran. it is from Hadith which is quotations of the prophet peace be upon him

in islam there are 4 source of knowledge

1) Quran
2) Hadith: prophets sayings and actions which elaborate on Quran
3) Account of the life of the prophet, equivalent to Bible
4) Scholarly writings on jurisprudence, manners, interpretations; you can say schools of thoughts

"Hoor" is the arabic word for this mistranslation. they are a creature in human form. their attributes are virginity (never been touched by man before), extreme beauty, extremely lovely and cute ... etc - you get the point - they were created as part of paradise's enjoyment and entertainment - after all that is why we call it paradise

however, the muslim women will be much much more beautiful and attractive than those "Hoor". this is because of their higher status (being human) and their strive for faith in this life