Proverbs 6:32 But whoso committeth adultery with a woman lacketh understanding: He that doeth it destroyeth his own soul. 33 A wound and dishonour shall he get; And his reproach shall not be wiped away.
A person who commits adultery shows that he doesn’t have good sense. He is destroying his own soul. He gets hurt in a way that he lives with the rest of his life. Honor your marriage. Stay away from any but your own spouse.
I think that the world paints a picture that sex outside of marriage among consenting adults is ok. God has a different opinion. Know that He knows best. Be careful not to do what the world says but to honor what God says.