It looks a bit like an inverted nipple, which could have "road dirt" and sweat built up around it, which give it kind of a gross smell.
I agree. My Ella's two top nipples are inverted and I have to make sure to keep them clean. They get a buildup of matter that stinks. I would suggest a trip to the vet just to make sure and go from there.
It appears to be a clogged pore...or like a black head pimple on a human.
Its common for some male dogs to get them in that area.
Sometimes they do smell when popped.
FYI: I'm no Vet. But thats what it looks like to me. There are vids online of people popping them too.
looks like some kind of bug bit ... and bad smell normally means infections. I agree with Smokeycat. Your vet will most likely give you an topical anti-biotic cream to put on. Is it bothering him? has he been licking it or chewing on it?
Have you tried to put warm cloth on it and hold it there to try to draw it out?
for now I wouldn’t do that alcohol I’m thinking that would only irritate it, more so then help. Do you have peroxide? That would kill the bacteria and maybe not dry it out the heathy tissue around it. I would also try to do the warm compress as many times per day you can to draw it out. If it doesn’t come out in a couple days, that when I would take him to the vet. That or sooner if the condition worsens.