Most come to him through social media links to his website. “It has taken on a life of its own,” he said. “I have heard from people in China — and even a man who has an uncle in Uzbekistan who is a dead ringer for former President George W. Bush.”

Two of his subjects, Roniel Tessler and Garrett Levenbrook, met three years ago at the University of Michigan, where Mr. Levenbrook was a student and Mr. Tessler was visiting with an a cappella group from the University of Maryland. Mutual friends steered them to Mr. Brunelle’s website.

When the two got together, at a pizza parlor in New York City, “we ordered the same toppings,” said Mr. Levenbrook, 25. “I found it difficult at first to look at Roniel because I felt I was looking into a mirror.”