I can promise you, what he's doing isn't related to being a femboy. What he is doing is underdressing (a form of crossdressing involving just crossdressing with only underwear.) Most people who take part in underdressing typically just wear the underwear intended for the opposite binary gender underneath their normal clothes in secret. However, in Jeffery’s case, he is specifically doing it for fetish reasons such as transvestic fetishism (getting off on wearing clothes of the opposite binary gender) and exhibitionism (getting off on the thrill of showing himself off in a revealing way to others in public or digitally. Similar to a flasher). He's also influenced as a pedo to push his fetishes here unfortunately because of the age of most users here…
If anything, he's making my community (the crossdressing community. I dress up in men’s clothing occasionally for cosplay or for comfort & enjoying the fashion.) look bad. There's definitely some overlap between crossdressers and femboys (and even drag a bit, although they do it to a level of extreme characterization) but there's also a few differences. It's kinda like squares and rectangles in a way. All femboys who dress up can be considered crossdressers but not all crossdressers are femboys. And what Jefferey is doing is definitely not femboy in any way.