I talk about this in my book, GIRLFRIEND 911, and here's a great article from Tanobuzz.com on how other people's energy can affect you when you're being intimate. A must read:
Pay close attention to those you share your intimate energy with. Intimacy at the sexual level intertwines your aural energy with the aural energy of the person you’ve been intimate with. These connections are extremely powerful. Regardless of how insignificant they might seem to you, they leave spiritual debris, especially within people who don’t practice any form of physical, emotional, or spiritual cleansing. The more you interact with someone intimately, the deeper the connection and the more their aura is intertwined with yours. Others can sense this energy which can repel positivity and attract negativity into your life.
“I always say, never sleep with someone you wouldn’t want to be” - Lisa Chase Patterson
We are all physical creatures by nature, but we are also far more than that. We are spiritual, energetic beings as well. When you get intimate with someone, you merge with their energy. Anytime you are intimate with another person, you absorb some of their spiritual energy and they absorb some of yours.
If you engage with uplifting, loving people, their wonderful energy is absorbed and uplifts you as well. If you engage with negative, unstable, pessimistic people, their energy will having you uninterested in your daily life. Keep in mind that if the person you are engaging with sleeps with a variety of people, the have absorbed the energy of all those people. Next time you jump into bed with someone, keep in mind that unless the cleanse their energy regularly, you will be getting intimate with anyone they’ve been intimate with as well.