Meaning one Black girl who is really into white guys. Swirlin'(Interracial dating) is her lifestyle and she is fully prepared to deal with any judgement over it.
"Jessica said she liked it nasty, so during some doggy style in the bathroom I put her head in the toilet and flushed over and over again. Jessica is now a swirlie girl."
When engaging in sex with the girl on top, and she twirls from the standard on top position to reverse cowgirl while keeping the man inside of her the entire time.