The Beatbox Lumberjack

It was the day after Thanksgiving, and the Brooklyn-bound A-train was much less crowded than I would have expected, given all the Black Friday announcements during the weeks before. I was sitting at one end of an otherwise empty triple-seat, and across from me was a grizzled sixtyish man in a lumberjack jacket with a fur Cossack hat that was pulled down over his eyes. I thought that he was asleep, but as we pulled out of the next stop, he started to sing what I can only guess was a song that he was making up on the spot in a voice that sounded like it was seldom used for speech, let alone song. At the same time, a bickering couple had joined me on my bench. As he sang, the lumberjack's voice grew stronger, and he started to do NKOTB-style arm gestures to accompany his song. (Since he was holding a paper cup of coffee at the same, this was not only odd, but also messy.) One of the men in the couple beside me looked across the car and suddenly started beatboxing along with the ever louder song.
"What are you doing?" asked the other man in the couple.
The first man stopped his percussing. "You always say that I'm too introverted, so I'm expressing myself." He then resumed. I felt like I was stuck in the episode of Modern Family in which Mitchell joins a flashmob to impress Cameron. His partner looked shocked, but then smiled.
The lumberjack got off at the next stop, having fully roused himself at this point, and also having spilled all of the remaining coffee. He continued to sing as he left the train, and once he reached the stairs of the platform, he started dancing down them as though he were in a 1950s musical. The couple did not bicker for the rest of the ride.