This article by Erika W. Smith for Refinery 29 delves into all the hows and whys of playing with your partners perineum. Read an excerpt below, then the full piece here:

“For such a small patch of skin, the perineum can lead to a lot of pleasure. Also called the taint, the perineum is the name for the area between the genitals and the anus. And no matter your gender, playing with this area can make for a great addition to your sex life. "The perineum is rich with sensitive nerve endings,” explains Alicia Sinclair, certified sex educator and CEO & founder of anal toy brand b-Vibe. “Regardless of the gender one was assigned at birth, there is tons of pleasure opportunity.”