Roelfzema started writing in his teens. From 16 years of age onward he was committed to becoming a writer. He attended the University of Leiden and was a member of the Leidsch Student Corps "Minerva society" while living at Rapenburg 56 across the canal from the Academiegebouw. During his hazing initiation the president of his student corps, Ernst de Jonge, threw a soup tureen at a group of new students, striking Roelfzema in the head and cutting his scalp. De Jonge had been an Olympic rower at the 1936 Summer Olympics in Berlin, and was very popular among the students. His accidental wounding of Roelfzema was the basis for their forming a friendship.