We brought you some interesting descriptions of what it feels like to have sex when you have a penis. You mainly feel fullness and warmth. A finger or will do it sometimes, but other times you just need to be stretched by a penis. Definitely not as intense as an orgasm but still gets your blood pumping and your heart racing and sends shivers through your body. Like when your muscles are tense and you just reach out and feel things open up and release tension.

Considering that the vagina is designed to stretch so much that another human can pass through it, you'd think it could easily fit any size erect penis. At rest, the vaginal canal measures 3. But when you're sexually aroused, it elongates, lubricates, and expands—so even sex with an XL guy is slippery and comfy. The average erect penis comes in at 5.

Contributors: WWS initiated and coordinated the formulation of the study hypothesis, designed the protocol, and participated in data collection, interpretation of the findings, and writing of the paper; he is guarantor of the study. PvA had the original idea for the present study, and participated in formulation of the study hypothesis, data collection, interpretation of the findings, and writing of the paper. IS, together with her partner, participated in the first two experiments and helped design the protocol. EM participated in the execution of the study, particularly data collection and interpretation of the magnetic resonance findings.