Apparently forgetting that he must, in fact, descend those steps, he hurls himself outward, arms and head thrust forward like a skydiver's. His fellow passengers observe his exit without comment. One by one they descend, sidestep his inert body, and make their ways onward. If the man were a dog, the riders might cluck their tongues at him, sympathetically urging him to get up and get going. He's a drunk, though, so everyone looks away.
Nobody is surprised when vodka meets yearning, self-loathing, or rage.
It's old hat, this encounter. Eventually, the drunk manages to stand up and stagger off. The imprint of his body remains. Shortly thereafter, a dog arrives, lies down, and curls up in it. In the late evening, dog-owning Muscovites bundle up for the last walk before bedtime.