Sex Outside Marriage
Dangers of fornication and adultery
Sexual play (intercourse, oral, etc.) is supposed to be for marriage. Whether or not you're a Christian, it's wise to keep this rule. It not only opens a person up to diseases and curses such as HIV, but it also creates unholy soul ties (spiritual bondage between one person and another), which can cause unclean (demonic) bondages to transfer from one person to the other.
Brief Biblical look at soul ties
1 Corinthians 6:16, "What? know ye not that he which is joined to an harlot is one body? for two, saith he, shall be one flesh."
Obviously the two didn't get married, but something spiritual "happened" when they were joined physically in the act of sex. They were "joined"; their souls were "tied." Often there are men who have an adultery with a prostitute (one night stand), and afterwards, even years later, are still thinking about that girl! That is because a soul tie has been created.
Dangers of unholy soul ties
Unholy soul ties can be 'demonic bridges' between one person to the next. For example, if you were to have extra-martial sex with somebody who was involved in the occult and had horrible fears of demons, and was afraid of her own shadow.. you could end up with the same kind of tormenting spirits as she has, and be just as fearful (although you could have been afraid of nothing before sleeping with her!). This is because you are not only opening yourself up to a curse for sexual sin, but also a soul tie with a person who is tormented by demons.
Don't think to yourself that the person you are having sex with is clean from demon spirits. Demons spirits can cause everything from depression to horrible fears (panic attacks, etc.) and a huge list of problems that people face everyday!
Struggle against compulsive lustful desires?
If you have a compulsive struggle with lust, bad thoughts, etc., you may be struggling with what they call an iniquity. An iniquity is like a weakness (lust, anger, pride, etc.) and it could have been handed down from your ancestors (Exodus 20:5) or it could have been opened up in your own life (Lev 5:17).
You might want to check out a book titled Breaking Generational Curses & Pulling Down Strongholds by Vito Rallo. It's a real eye opener to how these iniquities get started, how they operate, and how to go about breaking yourself off from them.