My heart beats
Martin's Heart is an afterglow or après technique but could be used as a smooth foreplay. Its delivery is any Gender-to-Gender contact but I'm told works best when received by a woman. After vigorous sex, where the pulse rate has been racing and before you light that cigarette, if you're a woman, let your partner place the left side of their ribcage against your clitoris. To get the right angle perhaps a pillow across your stomach will help reduce ribs digging in, or arching of backs until you get a good heart to clit contact, then just relax and enjoy the intimacy, that's it, I'll leave it up to you to try it out and find out how it feels.
Tip, unless you are a paramedic and can't find a strong pulse, use a finger, not your thumb on your partner's left side of their chest about 3 ribs up, find the strongest response and place this point against you.