When your dick is over 9 inches wide, and can open a girls ass so wide. You can put both fists and your head inside her asshole.
When that gets some good speed with the Black Hole Spreader

Man1: “BRO, I black hole opened Rachel’s ass so hard last night, I lost my shoes in her!”
Man2: “Fucking sick dude!”
by TwiddleNigga-FuckDick-ManPussy January 11, 2019
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