The average Indian person will tell you that it is wrong to have sex before marriage. They think sex is something dirty, even if they are married. Before being married however it is thought to be a sin!
I believe the concept of open relationships is against human nature. If you continue your sexual relationship for a longer time, you will develop feelings and that is the point where jealousy can happen, too! If you love someone, if you feel for someone and this person sleeps with someone else, it is natural that you get jealous!
Polygamous relationships don’t really work. If you are really in love with someone, you will be jealous, you won’t be able to avoid that! If you love your partner, it is impossible!
You cannot love, have sex with different people and not be jealous all at the same time!
When two people meet and decide to have sex and decide on the next day that they want to have sex with a fully different person, it is their private matter – as long as they don't cheat anyone, wear a condom and don’t spread any diseases!