When you engage in sex with a person who is not your spouse, not only is your physical body open to that person, but your soul is open to them as well. When you enter that person or vice versa, a soulish bond is established, connecting you beyond the natural act. This person becomes a part of your feelings (emotions), your memory, and even some of your decisions. The exchange of saliva and other bodily fluids is not the only transaction that takes place, your soul becomes fragmented because now they possess a part of you.
The same way that the Bible declares a man and his wife to be one flesh is what happens when souls are knitted. To have your soul knitted is to become fused with another and if your soul is fused with one who is not in covenant with you, they cannot keep that part of you that you gave them safe. Your soul becomes restless, vulnerable, and exposed to great danger.
Genesis 34:2-3, "And when Shechem the son of Hamor the Hivite, prince of the country, saw her, he took her, and lay with her, and defiled her. And his SOUL CLAVE unto Dinah the daughter of Jacob, and he loved the damsel, and spake kindly unto the damsel."
Clave - attracted, infatuated, joined, drawn, become fond, or connected.
This happened AFTER THE SEXUAL ACT. You may read further to find out that Shechem was killed, Gen. 34:26.
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."
When your soul is fragmented by sexual relations, you are vulnerable to demonic influences of jealousy, rage, competition, lying, manipulation, compromise, embarrassment, shame, promiscuity, rape, and even murder.
The Lord wants to deliver you and restore every fragmented area of your life. Commit your ways to Him, repent of giving up something so precious and valuable to another outside of marital covenant. Know that your body is the Temple of God and each time you lay it down, bend it over, stand it up, or whatever, you compromise who God called you to be for a few moments of pleasure. You are more than a toy to be rolled around in the sheets. You have more value than you know and it's high time you place a demand on yourself to do better and expect better. I pray restoration in every broken area of your life and that you come into the knowledge of how sincerely the Lord loves and cares about you.