did the second person have any other interests apart from literature?
Yes, in cryptography.
Edgar Allan Poe
Poe had a keen interest in cryptography. 
who was rufus wilmot griswold? An anthologist, editor, poet, and critic. who was poe? A writer, editor, poet, and literary critic. was there anything particular about the relationship between the two men? Though in the beginning both enjoyed a cordial relationship with Griswold publishing Poe's poems and the latter writing a favourable critical review for the former, later it was strained due to various factors.
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Edgar Allan Poe [SEP] Cryptography
Poe had a keen interest in cryptography. He had placed a notice of his abilities in the Philadelphia paper "Alexander's Weekly (Express) Messenger", inviting submissions of ciphers which he proceeded to solve. In July 1841, Poe had published an essay called "A Few Words on Secret Writing" in "Graham's Magazine". Capitalizing on public interest in the topic, he wrote "The Gold-Bug" incorporating ciphers as an essential part of the story. Poe's success with cryptography relied not so much on his deep knowledge of that field (his method was limited to the simple substitution cryptogram) as on his knowledge of the magazine and newspaper culture.