Can another human please explain to me how a man “pops” his boner?

My (28F) boyfriend (28M) does something I have never witnessed another man do in all my years of life.

If he has a boner he doesn’t want, he simply double hands the shaft and bends slightly. His dick will make an audible pop sound (softer than a knuckle crack, but similar-sounding) and his boner will go down within 30 seconds afterwards. The first time I saw him do it I was like “…what the actual fork is that and why did it work”. My thoughts over the year we’ve been together have now changed to “…sorcery”. Allegedly, it does not cause him pain whatsoever. The only thing I can find on Dr. Google is that this is actually (possibly) a penile fracture; however, he’s had a sex mishap in the past where there was a hard miss upon reentry and he ACTUALLY fractured his dick which I understand for him (and all men) was/is incredibly painful. He said when he pops his dick it’s not even remotely the same thing —it causes no discomfort and he doesn’t even feel it.

To get ahead of understandable questions, this seems to have no adverse effects. He is popping the base of his dick, the pop happens near his pelvic region. He has zero issues with erectile dysfunction or any other arousal concerns. He does not have any desensitization or issues with ejaculation. We have a very healthy sex life (2-5x per week) and there has never been an issue with any aspect of his functionality or performance. It doesn’t cause him pain at anytime, even afterwards. He has reportedly been doing it since he was a teenager.

There was a thread for this on this subreddit from like 10 years ago, but I want to ask again and see if any modern users can weigh in on the topic. Thank you so much for helping me solve the concerning mystery of the boner pop.