I believe that laying your ear on your partner's chest is one of the hottest things a cardiophile can experience, mostly when their heart is pounding and you can feel it so clearly on your face, you can notice your head moving up and down from the beating. Let alone having them listening to your heart while you can feel it forcefully beating against them, you can't help but imagine what they're hearing and feeling, personally I get so wet everytime, I get the urge to touch myself and let go of all the sexual tension (we did that off camera).
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