The act of slowly, softly, comfortably, consenting (recommended, though not needed) sexy, and sliding of ones thick, hard, stiff, twitching, convulsing, vain, blood rushing, red cell rush, of a huge, small, and well sized shlong, which slowly slides inside a tight man pussy (if she contains a forest) or a regular pussy (a deforested Amazon)
You fam, I had some sweet penetration by my girlfriend, honestly I was scared when she brought out the strap, but honestly, it felt pretty good 10/10 would recommend