I've never had Hepatitis or any STD from licking the anus. I've licked clean and unclean anuses over the last 40 years never having caught it, thankfully.
What is "Pound cake"? I am guessing that it is butt-slapping doggie style rear entry as male's belly and thighs repeatedly hit against lady's backside... Congratulations on your success with the mature women in your neighborhood! If you had not been attractive, discreet, and virile, I doubt you would have gotten very far with them! A cautionary note about licking dirty anal venues is to avoid hepatitis with some pre-cleaning...
Older women will do things with a younger man that they might not do with another male around their age. In my teens and very early twenties, there were several older married women in my neighborhood who I would have anal sex with, no condom. They loved that I was younger, well-hung and truly enjoyed smelling and licking their dirty asses. They weren't exactly attractive but had bodies that any man would love to fuck. They were amazed and turned on that I enjoyed eating my own cum from their assholes, apparently men of their age at the time weren't into that. One of the women taught me how to play 'pound cake." While not my favorite, it remains a turn-on and some women are truly turned on by that.
This looks real! Older woman dropped her knickers and bent over to accept penetration by a young man... Why did they record this on video? Such a question can fuel delicious speculation and fantasy...