Being made to feel guilty about consentual sex is wrong in my opinion, but I do think there is a higher chance of unwanted pregnancy if many participate in a promisicuous lifestyle. Having a steady partner is more reasonable and probably more likely.
On a high control level when you can master/control a person or living beings natural functions you have made that person/creature your slave/pet.
One of the keys to domkesticating any animal is to control its food source and when it is allowed to eat. Dont know if you watch the new cosmos with neil degras tyson, but the 2nd episode was on how early man domesticated the wolf. he pointed out how the wolf gave up certain freedoms for the benifit and ease of living with and working with (hunting/protecting) humans. The show pointed out how the wolf went from picking his OWN mate and who he reproduced with to ACCEPTING the mate the humans picked for him to breed with.
Animal husbandry at its finest and in a very subtle way the nature of most religions/high control groups. catholics marry catholics jews jews and musilem musilems. what better way to have your religion/group thrive and grow than to pick and have re-enforced the tenates of how sex relations and marriage should be handled.
so back to control of natural functions like sex when a religion instills certain protocalls when it comes to sex into its young and most impressionable members that creates a unique bond and tie between the religion and the person (thats a point strongly touched on in the 2nd vid.)