I’ve heard this mentioned in a few places, usually from detransitioners (who don’t realize that they’re being exploited until after the fact). Straight guys playing along with the delusions of uwu smol bean femmebois for access to free anal sex from girls and women without strings attached.

These people are really just fucking themselves over and playing right into the hands of predators, it’s so sad.

It seems like this wasn't even anal sex, just traditional intercourse, how she sees it as gay I will never know